The body has amazing abilities to heal, a 3 week bender shouldnt do irreversible damage given you had a year clean prior. If doc didn't see any signs for concern, I would believe him/her.
You are still removing alcohol from your system even after a week so give it a bit more time
Try to think positively, it's hard but with practise it does help, particularly with the mental side which plays a big role in the physical side in my opinion. It does for me.