When did you get this baby ball and how long has he gone without eating? Is he drinking? Since he started eating this Saturday i'd suggest to make sure he gets plenty of water and once he starts feeding regularly he should be okay because it just sounds like he hasn't eaten/drank for a while. I would recommend trying to feed him again soon but make sure it's not too big for him, try and feed him something smaller more often until he eats regularly. Good luck.