N.H.
The PPs had some great suggestions. Also, how do you react when he does something "bad"? Are you reacting a lot? Sometimes even negative attention is what kids want, especially when it comes to potty training setbacks. If my boys have an accident I try to be very matter-of-fact about it (tell them where pee goes, and at his age I would get him to clean it up and get dry clothing for himself) and move one. Same goes for other bad behavior. Just decide on a punishment, do it and move on - try not to be emotional about it. I wish you luck - maybe the doctor will have some other good suggestions.