my ball python

Question
It's her feeding time but she wouldn't eat so I picked her up and checked her out and there is feces dried on her rectum and all around her rectum is sunken in do you have any idea what could be wrong with her

Answer
No, I do not.  I do know that that sounds serious enough that I would recommend a trip to the vet.  Unusual excretory behavior such as that is usually a sign of a serious internal problem or infection, with infection being my first guess.  Only a qualified vet is going to be able to diagnose and treat that problem.  Good luck!