Welcome to YT!
I'm sure many very experienced folks will come on and post more help for you.
From what you are saying, it sounds to me like yourmpupmhas not been socialized - was maybe part of a breeding restraint situation. The panting and not interacting with you could be anxiety response, again related to not being socialized. That would be my first guess if the vet says he is healthy.
Confining him to a smaller area will help with his "accidents", helping him make better potty choices etc. You have no background (or name) on this pup so the pup is probably real confused. Smaller area with bed and peep area and a tight schedule for going outside. Have you taken the pup for walks yet? That may help. E understand this pup may never have been taken for a walk somthat no idea what it is all about. Be sure to use a harness, not a collar for this.
Good luck! I'm sure others will come forward to help you.
__________________ .   Cali  , and Cali's keeper and staff, Jay No, not a "mini" Yorkie - She loves to motor in her Mini Cooper car  |