Welcome, you are getting great advice so far, the only thing I would add is that you said you fed him a pinky mouse? If so that is much to small, you need a small mouse or a pinky rat for a baby ball python. The rule is the prey item needs to be just a little bit smaller then the thickest part of the snakes body, every 5 or 7 days. Hope I said that right, if not someone will correct me soon. Good luck with him!