<PAGE>

                                                                    EXHIBIT 10.5

            FIRST AMENDMENT TO CREDIT AGREEMENT AND LIMITED CONSENT


     THIS FIRST AMENDMENT TO CREDIT AGREEMENT AND LIMITED CONSENT (this
"Amendment"), dated as of May 17, 2001, among NEXSTAR FINANCE, L.L.C., a
----------
Delaware limited liability company (the "Borrower"), NEXSTAR BROADCASTING GROUP,
                                         --------
L.L.C., a Delaware limited liability company (the "Ultimate Parent"), the other
                                                   ---------------
Parent Guarantors (as such term is defined in the hereinafter described Credit
Agreement) parties to this Amendment, the several Banks (as such term is defined
in the hereinafter described Credit Agreement) parties to this Amendment, and
BANK OF AMERICA, N.A., as Administrative Agent for the Banks (in such capacity,
the "Administrative Agent").
     --------------------

                               R E C I T A L S:

     A.  The Borrower, the Ultimate Parent, the other Parent Guarantors, the
Administrative Agent, Barclays Bank PLC, as Syndication Agent, First Union
National Bank, as Documentation Agent, and the several Banks parties thereto
entered into that certain Credit Agreement dated as of January 12, 2001 (as the
same may be amended, modified, restated, supplemented, renewed, extended,
increased, rearranged and/or substituted from time to time, the "Credit
                                                                 ------
Agreement").  Capitalized terms used and not otherwise defined herein shall have
---------
the meanings ascribed to them in the Credit Agreement.

     B.  Nexstar Finance Holdings proposes to issue $36,988,000 aggregate
principal amount of its 16% Senior Discount Notes due 2009 (the "Holdings Senior
                                                                 ---------------
Discount Notes") pursuant to an Indenture (the "Holdings Senior Discount Notes
--------------                                  ------------------------------
Indenture") having such covenants and other terms and provisions as are
---------
described in that certain Offering Memorandum dated as of May 17, 2001.  The
Holdings Senior Discount Notes are to be issued in units (the "Units") linked to
                                                               -----
shares of non-voting Class B Common Stock of Nexstar Equity Corp., a Delaware
corporation ("Nexstar Equity"), 100% of the issued and outstanding voting Class
              --------------
A Common Stock of which is owned directly by ABRY L.P. III, and the sole asset
of which is a 1% membership interest in the Ultimate Parent.  In connection with
such joint issuance as Units of the Holdings Senior Discount Notes and the
shares of Nexstar Equity Class B Common Stock, Nexstar Equity and certain
Nexstar Entities intend to enter into certain agreements and arrangements, as
more fully described herein.

     C.  As a condition to the issuance of the Holdings Senior Discount Notes,
the Ultimate Parent is required to guarantee the payment of the Holdings Senior
Discount Notes and the performance and observance of the covenants and other
terms and provisions of the Holdings Senior Discount Notes Indenture (the
"Holdings Senior Discount Notes Guarantee") until such time as certain
-----------------------------------------
promissory notes issued by Nexstar Finance Holdings to the Ultimate Parent no
longer rank equal in right of payment with the Holdings Senior Discount Notes,
which Nexstar Finance Holdings proposes to accomplish by (i) creating, on or
before November 30, 2001, a new Wholly-Owned Subsidiary, (ii) causing such new
Wholly-Owned Subsidiary to assume the Holdings Senior Discount Notes and all of
Nexstar Finance Holdings' obligations with respect thereto and (iii) obtaining
from the holders of the Holdings Senior Discount Notes the full and
unconditional release therefrom of Nexstar Finance Holdings.
<PAGE>

     D.  The issuance by Nexstar Finance Holdings of the Holdings Senior
Discount Notes may presently be prohibited by Section 8.05 of the Credit
Agreement inasmuch as the Indebtedness evidenced thereby may not fall within the
definition of "Permitted Holdings Unsecured Indebtedness" set forth in Section
1.01 of the Credit Agreement.

     E.  The agreements and arrangements among Nexstar Equity and certain
Nexstar Entities referred to in Recital B above are presently prohibited by
Section 8.06 of the Credit Agreement, and the authorization, declaration and
payment by the Borrower and the Parent Guarantors of Dividends required in order
to enable the Ultimate Parent to reimburse certain expenses of Nexstar Equity
pursuant to one of such agreements is presently prohibited by Section 8.10 of
the Credit Agreement.

     F.  The providing by the Ultimate Parent of the Holdings Senior Discount
Notes Guarantee is also presently prohibited by Section 8.05 of the Credit
Agreement.

     G.  The Borrower and the Ultimate Parent have requested that the Banks: (i)
consent to the entering into by certain Nexstar Entities of the agreements and
arrangements referred to in Recital B above, the reimbursement by the Ultimate
Parent of certain expenses of Nexstar Equity pursuant to one of such agreements,
and the authorization, declaration and payment of Dividends by the Borrower and
each Parent Guarantor for the purpose of providing sufficient funds to the
Ultimate Parent to enable it to reimburse such expenses; (ii) consent to the
providing by the Ultimate Parent of the Holdings Senior Discount Notes Guarantee
and its existence as an outstanding obligation of the Ultimate Parent for a
limited period of time; (iii) agree to amend the definitions of "Nexstar Finance
Holdings" and "New Holding Company" to accommodate and reflect the
organizational restructuring described in Recital C above; and (iv) agree to
amend the definition of "Permitted Holdings Unsecured Indebtedness" set forth in
Section 1.01 of the Credit Agreement in order to permit the issuance by Nexstar
Finance Holdings of the Holdings Senior Discount Notes, each as more fully
described hereinbelow.

     H.  The several Banks parties to this Amendment (which Banks constitute the
Majority Banks required under the Credit Agreement to grant the consents and
effect the amendments intended hereby) are willing to grant the above-described
consents and agree to the above-described amendments, subject in each case to
the performance and observance in full of each of the covenants, terms and
conditions, and in reliance upon all of the representations and warranties of
the Borrower and the Parent Guarantors, set forth herein.

     NOW, THEREFORE, in consideration of the premises and the covenants, terms,
conditions, representations and warranties herein contained, the parties hereto
agree hereby as follows:

     Section 1.  AMENDMENTS TO CREDIT AGREEMENT. Subject to the covenants, terms
and conditions set forth herein and in reliance upon the representations and
warranties of the Borrower and the Parent Guarantors herein contained, the
Borrower, the Parent Guarantors and the several Banks parties to this Amendment
(which Banks constitute the Majority Banks required under the Credit Agreement
to effect the following amendments) hereby agree to amend the Credit Agreement,
effective as of the Amendment Effective Date (as hereinafter defined), as
follows:

                                       2
<PAGE>

     (a)   The definition of "Nexstar Finance Holdings" set forth in Section
1.01 of the Credit Agreement is amended by deleting it in its entirety and
replacing it with the following:

           "  "Nexstar Finance Holdings" means: (i) Nexstar Finance Holdings,
               ------------------------
     L.L.C., a Delaware limited liability company and a Nexstar Entity, until
     such time as the Indebtedness evidenced by the 16% Senior Discount Notes
     issued May 17, 2001 by Nexstar Finance Holdings, L.L.C. in the  aggregate
     principal amount of $36,988,000 has been assumed by a new direct Wholly-
     Owned Subsidiary of Nexstar Finance Holdings, L.L.C., Nexstar Finance
     Holdings, L.L.C. has been fully and unconditionally released therefrom and
     Nexstar Finance Holdings, L.L.C. has assigned and transferred to such new
     direct Wholly-Owned Subsidiary 100% of the Capital Stock of the Borrower;
     and (ii) such new direct Wholly-Owned Subsidiary of Nexstar Finance
     Holdings, L.L.C. at all times thereafter."

     (b)   The definition of "New Holding Company" set forth in Section 1.01 of
the Credit Agreement is amended by deleting it in its entirety and replacing it
with the following:

           "  "New Holding Company" means Nexstar Finance Holdings, L.L.C., a
               -------------------
     Delaware limited liability company and a Nexstar Entity, at all times from
     and after such time as the Indebtedness evidenced by the 16% Senior
     Discount Notes issued May 17, 2001 by Nexstar Finance Holdings, L.L.C. in
     the  aggregate principal amount of $36,988,000 has been assumed by a new
     direct Wholly-Owned Subsidiary of Nexstar Finance Holdings, L.L.C., Nexstar
     Finance Holdings, L.L.C. has been fully and unconditionally released
     therefrom and Nexstar Finance Holdings, L.L.C. has assigned and transferred
     to such new direct Wholly-Owned Subsidiary 100% of the Capital Stock of the
     Borrower."

     (c)   The definition of "Permitted Holdings Unsecured Indebtedness" set
forth in Section 1.01 of the Credit Agreement is amended by deleting in its
entirety clause (v) thereof and renumbering clause (vi) thereof as new clause
(v).

           Section 2.  LIMITED CONSENTS.  Subject to the covenants, terms and
conditions set forth in this Amendment, and in reliance upon the representations
and warranties of the Borrower and the Parent Guarantors herein contained, the
several Banks parties to this Amendment (which Banks constitute the Majority
Banks required under the Credit Agreement to effect the following consents)
hereby consent to the following:

           (a)   The providing by the Ultimate Parent of the Holdings Senior
Discount Notes Guarantee in substantially the form contained in the draft
Holdings Senior Discount Notes Indenture provided to the Administrative Agent
and its counsel on May 16, 2001, and the existence of the Holdings Senior
Discount Notes Guarantee as an obligation of the Ultimate Parent until the
earlier of (i) November 30, 2001 and (ii) the date the Indebtedness evidenced by
those certain two promissory notes in the respective face principal amounts of
$20,531,402 and $11,355,000, each dated December 31, 2000 and issued by Nexstar
Finance Holdings to the Ultimate Parent no longer ranks equal in right of
payment to the Indebtedness evidenced by the Holdings Senior Discount Notes.

                                       3
<PAGE>

     (b)   The entering into and performance by the Nexstar Entities indicated
below of the following agreements and arrangements in connection with the joint
issuance as Units of the Holdings Senior Discount Notes and the shares of
Nexstar Equity Class B Common Stock, each in substantially the form provided to
the Administrative Agent and its counsel on or about May 16, 2001:

           (i)   Purchase Agreement by and among Nexstar Finance Holdings,
     Nexstar Finance Holdings, Inc., Nexstar Equity, the Ultimate Parent and the
     initial purchasers of Units party thereto, relating to the issuance and
     sale of the Units;

           (ii)  Unit Agreement by and among Nexstar Finance Holdings, Nexstar
     Finance Holdings, Inc., Nexstar Equity, the Ultimate Parent and United
     States Trust Company of New York, as the Unit Agent, governing the Units;

           (iii) Units issued and sold to the initial purchasers thereof;

           (iv)  Investor Rights Agreement by and between the Ultimate Parent
     and Nexstar Equity;

           (v)   Amended and Restated Limited Liability Company Agreement of the
     Ultimate Parent by and among the Ultimate Parent, Nexstar Equity and the
     other members of the Ultimate Parent party thereto; and

           (vi)  Reimbursement Agreement by and between the Ultimate Parent and
     Nexstar Equity, providing for the reimbursement by the Ultimate Parent of
     out-of-pocket expenses incurred by Nexstar Equity in connection with
     maintaining its corporate existence, filing tax returns, maintaining
     directors' and officers' insurance and such other activities deemed
     necessary by Nexstar Equity's board of directors and agreed to by the
     Ultimate Parent, provided, that the aggregate amount of such expenses
                      --------
     reimbursed by the Ultimate Parent in any fiscal year may not exceed
     $40,000.

     (c)   The authorization, declaration and payment by the Borrower and each
Parent Guarantor to their respective shareholders, partners or members, as
applicable, for the purpose of providing sufficient funds to the Ultimate Parent
to enable it to reimburse such expenses of Nexstar Entity pursuant to the above-
described Reimbursement Agreement, subject to the dollar limitation set forth
hereinabove, and so long as no Default or Event of Default exists both before
and after giving effect to such Dividends.

The consents set forth in this Section 2 are limited to the extent specifically
                               ---------
set forth above and no other terms, covenants or provisions of the Credit
Agreement are intended to be affected hereby.

     Section 3.  CONDITIONS PRECEDENT.   The parties hereto agree that this
Amendment and the consents and amendments to the Credit Agreement contained
herein shall not be effective until the satisfaction of each of the following
conditions precedent:

                                       4
<PAGE>

     (a)   Execution and Delivery of this Amendment. The Administrative Agent
shall have received a copy of this Amendment executed and delivered by each of
the applicable Credit Parties and by Banks constituting Majority Banks.

     (b)   Representations and Warranties.  Each of the representations and
warranties made in this Amendment shall be true and correct on and as of the
Amendment Effective Date as if made on and as of such date, both before and
after giving effect to this Amendment.

     Section 4.   REPRESENTATIONS AND WARRANTIES. To induce the Administrative
Agent and the several Banks parties hereto to enter into this Amendment and to
grant the consents and amendments contained herein, each of the Borrower and the
Parent Guarantors represents and warrants to the Administrative Agent and the
Banks as follows:

     (a)   Authorization; No Contravention.  The execution, delivery and
performance by the applicable Credit Parties of this Amendment have been duly
authorized by all necessary partnership, corporate or limited liability company
action, as applicable, and do not and will not (i) contravene the terms of any
Charter Documents of any Credit Party, (ii) conflict with or result in any
breach or contravention of, or the creation of any Lien under, any document
evidencing any Contractual Obligation to which any Credit Party is a party or
any order, injunction, writ or decree of any Governmental Authority to which any
Credit Party is a party or its property is subject, or (iii) violate any
Requirement of Law.

     (b)   Governmental Authorization.  No approval, consent, exemption,
authorization or other action by, or notice to, or filing with or approvals
required under state blue sky securities laws or by any Governmental Authority
is necessary or required in connection with the execution, delivery, performance
or enforcement of this Amendment.

     (c)   No Default. No Default or Event of Default exists under any of the
Loan Documents. No Credit Party is in default under or with respect to (i) its
Charter Documents or (ii) any material Contractual Obligation of such Person.
The execution, delivery and performance of this Amendment shall not result in
any default under any Contractual Obligation of any Credit Party in any respect.

     (d)   Binding Effect. This Amendment and the Credit Agreement as amended
hereby constitute the legal, valid and binding obligations of the Credit Parties
that are parties thereto, enforceable against such Credit Parties in accordance
with their respective terms, except as enforceability may be limited by
applicable bankruptcy, insolvency, or similar laws affecting the enforcement of
creditors' rights generally or by equitable principles of general applicability.

     (e)   Representations and Warranties. The representations and warranties
set forth in the Credit Agreement and the other Loan Documents are true and
correct in all material respects on and as of the Amendment Effective Date, both
before and after giving effect to the amendments contemplated in this Amendment,
as if such representations and warranties were being made on and as of the
Amendment Effective Date.

                                       5
<PAGE>

     Section 5.  MISCELLANEOUS

     (a)   Ratification and Confirmation of Loan Documents. Except for the
specific consents and amendments expressly set forth in this Amendment, the
terms, provisions, conditions and covenants of the Credit Agreement and the
other Loan Documents remain in full force and effect and are hereby ratified and
confirmed, and the execution, delivery and performance of this Amendment shall
not in any manner operate as a waiver of, consent to or amendment of any other
term, provision, condition or covenant of the Credit Agreement or any other Loan
Document.  Without limiting the generality of the foregoing, the consents set
forth in Section 2 of this Amendment shall be limited precisely as set forth
         ---------
above, and nothing in this Amendment shall be deemed (i) to constitute a waiver
of compliance or consent to noncompliance by any of the Credit Parties with
respect to any other term provision, condition or covenant of the Credit
Agreement or other Loan Documents; (ii) to prejudice any right or remedy that
the Administrative Agent or the Banks may now have or may have in the future
under or in connection with the Credit Agreement or any other Loan Document; or
(iii) to constitute a waiver of compliance or consent to noncompliance by any of
the Credit Parties with respect to the terms, provisions, conditions and
covenants of the Credit Agreement made the subject hereof, other than as
specifically set forth herein and for the time periods specifically set forth
herein.

     (b)   Fees and Expenses.  The Borrower and the Parent Guarantors jointly
and severally agree to pay on demand all reasonable costs and expenses of the
Administrative Agent in connection with the preparation, reproduction,
execution, and delivery of this Amendment and any other documents prepared in
connection herewith, including, without limitation, the reasonable fees and out-
of-pocket expenses of counsel for the Administrative Agent.

     (c)   Headings.  Section and subsection headings in this Amendment are
included herein for convenience of reference only and shall not constitute a
part of this Amendment for any other purpose or be given any substantive effect.

     (d)   APPLICABLE LAW.  THIS AMENDMENT SHALL BE GOVERNED BY, AND SHALL BE
CONSTRUED AND INTERPRETED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK,
WITHOUT REGARD TO CONFLICTS OF LAW PRINCIPLES.

     (e)   Counterparts and Amendment Effective Date.  This Amendment may be
executed in any number of counterparts and by different parties hereto in
separate counterparts, each of which when so executed and delivered shall be
deemed an original, but all such counterparts together shall constitute but one
and the same instrument; signature pages may be detached from multiple separate
counterparts and attached to a single counterpart so that all signature pages
are physically attached to the same document.  This Amendment shall become
effective when (i) each of the conditions precedent set forth in Section 3 of
                                                                 ---------
this Amendment have been satisfied and (ii) the Administrative Agent has
received counterparts of this Amendment executed by the Borrower, the Parent
Guarantors, each of the other Guarantors and the Banks constituting Majority
Banks (the "Amendment Effective Date").
            ------------------------

                                       6
<PAGE>

     (f)   Affirmation of Guarantees. Notwithstanding that such consent is not
required thereunder, each of the Parent Guarantors and the other Guarantors
hereby consent to the execution and delivery of this Amendment by the parties
hereto and reaffirm their respective obligations under each of their respective
Guaranty Agreements.

     (g)   FINAL AGREEMENT. THIS AMENDMENT, TOGETHER WITH THE CREDIT AGREEMENT
AND OTHER LOAN DOCUMENTS, REPRESENTS THE FINAL AGREEMENT BETWEEN THE PARTIES AND
MAY NOT BE CONTRADICTED BY EVIDENCE OF PRIOR, CONTEMPORANEOUS, OR SUBSEQUENT
ORAL AGREEMENTS OF THE PARTIES. THERE ARE NO UNWRITTEN ORAL AGREEMENTS BETWEEN
THE PARTIES.


     [Remainder of Page Intentionally Left Blank; Signature Pages Follow]

                                       7
<PAGE>

     IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
duly executed and delivered by their proper and duly authorized officers
effective as of the Amendment Effective Date.

                               BORROWER:

                               NEXSTAR FINANCE, L.L.C.

                               By:______________________________________________
                               Name:
                               Title:

                               PARENT GUARANTORS:

                               NEXSTAR BROADCASTING GROUP, L.L.C.
                               NEXSTAR BROADCASTING OF
                                NORTHEASTERN PENNSYLVANIA, INC.
                               NEXSTAR BROADCASTING OF JOPLIN, INC.
                               NEXSTAR BROADCASTING OF ERIE, INC.
                               NEXSTAR BROADCASTING OF
                                BEAUMONT/PORT ARTHUR,INC.
                               NEXSTAR BROADCASTING OF WICHITA
                                FALLS, INC.
                               NEXSTAR BROADCASTING OF ROCHESTER,
                                INC.
                               NEXSTAR BROADCASTING OF ABILENE, INC.
                               ERC HOLDINGS, INC.
                               NEXSTAR MIDWEST HOLDINGS, INC.
                               NEXSTAR BROADCASTING OF
                                CHAMPAIGN, INC.
                               NEXSTAR BROADCASTING OF PEORIA, INC.
                               NEXSTAR BROADCASTING OF MIDLAND-
                                ODESSA, INC.
                               NEXSTAR BROADCASTING OF LOUISIANA,
                                INC.
                               NEXSTAR FINANCE HOLDINGS, L.L.C.
                               NEXSTAR FINANCE HOLDINGS, INC.


                               By: _____________________________________________
                               Name:
                               Title:

                                       8
<PAGE>

                                     ADMINISTRATIVE AGENT AND BANKS:

                                     BANK OF AMERICA, N.A.,
                                     as Administrative Agent and as a Bank

                                         /s/ Steven P. Renwick
                                     By: _______________________________________
                                     Name: Steven P. Renwick
                                     Title: Vice President


                                     BARCLAYS BANK PLC,
                                     as a Bank

                                         /s/ Daniele Iacovone
                                     By: _______________________________________
                                     Name: Daniele Iacovone
                                     Title: Director


                                     FIRST UNION NATIONAL BANK,
                                     as a Bank


                                     By: _______________________________________
                                     Name:
                                     Title:


                                     FIRSTAR BANK, N.A.,
                                     as a Bank


                                     By: _______________________________________
                                     Name:
                                     Title:


                                     CIBC INC.,
                                     as a Bank


                                     By: _______________________________________
                                     Name:
                                     Title:

                                       9
<PAGE>

OTHER GUARANTORS (for purposes of Section 5(f) hereof):

NEXSTAR BROADCASTING OF ABILENE, L.L.C.
NEXSTAR BROADCASTING OF BEAUMONT/ PORT ARTHUR, L.L.C.
NEXSTAR BROADCASTING OF CHAMPAIGN, L.L.C.
ENTERTAINMENT REALTY CORPORATION
NEXSTAR BROADCASTING OF ERIE, L.L.C.
NEXSTAR BROADCASTING OF JOPLIN, L.L.C.
NEXSTAR BROADCASTING OF LOUISIANA, L.L.C.
NEXSTAR BROADCASTING OF MIDLAND-ODESSA, L.L.C.
NEXSTAR BROADCASTING OF THE MIDWEST, INC.
NEXSTAR BROADCASTING GROUP, INC.
NEXSTAR BROADCASTING OF NORTHEASTERN PENNSYLVANIA, L.L.C.
NEXSTAR FINANCE, INC.
NEXSTAR BROADCASTING OF PEORIA, L.L.C.
NEXSTAR BROADCASTING OF ROCHESTER, L.L.C.
NEXSTAR BROADCASTING OF WICHITA FALLS, L.L.C.

By: ____________________________________
Title: __________________ of each of the
       above-named entities


BASTET BROADCASTING, INC.


By: _____________________________________
Name:
Title:

MISSION BROADCASTING OF WICHITA FALLS, INC.



By: _____________________________________
Name:
Title:

                                       10