Infants cry because they are uncomfortable or distressed.
However, how does a parent know what is normal and what is not. Most infants in the first two months of life do not develop fevers. If they do and it isn't related to being overdressed call your clinician. Sick infants under the age of 2 months may have no fever but suck poorly on breast or bottle, are listless, vomit, have poor color or just do not seem the same to you. If you are concerned give us a call.