Practically, there is no issue in using PAN Card (before marriage) even after marriage. But it is recommended to change the name on card to avoid future problems i.e. opening a bank account requires same name as on PAN Card.
It's a simple process to change the name on PAN Card. Simply visit NSDL PAN Service . Fill an online application for 'PAN Card Change Request Form' and send the required documents to the addressed mentioned in the form.
Note that you PAN Number remain same. It's just your name will change.