Wow! We got banded the same day! I too having been having pain when burping. I talked to my nurse and she said that lots of people have the same problem. She said some people have to practically relearn how to burp. I assume the ache is gas, but I couldn't say for sure.
I've been having kind of a sharp, jabbing pain about 3 inches to the right of my navel. I notice it mostly when I'm digesting food in that area. I called my Dr today, but still no call back yet.
Good luck!
Heather