I haven't gone thru the surgery, as my insurance company denied it, and I can't afford to pay myself, but I want to assure you to just give it time. It's only been three weeks. Your body is probably in a fighting mode after the intrusion it has gone through. Do not give up. You certainly wouldn't want to waste this surgery and continue to gain, right?
I will keep you in my thoughts. I do think it will work out just fine for you. Give it time!