It sounds like she may be eggbound, and in that case needs to be seen by an avian veterinarian.
Prior to getting her to the doctor, apply heating to the cage – can be a heating pad leaned up against the outside of the cage, draped with a towel to warm her.
(For additional tricks to help a hen through egg binding, read this post.)
Answered by Cathy Johnson-Delaney, DVM, Dipl. ABVP-Avian Practice, Dipl. ABVP-Exotic Companion Mammals.