I was miserable from after the surgery from the gas that's used in the abdomen. I have a subclavian port (right above my left boob where your bra cup meets the strap...just the way my doctor likes to put them) and the gas that the body absorbs takes a while in some individuals. It hurt me all the way up to my left shoulder. Also, when I get too full, I hurt in my shoulder, neck, and lower back??? Weird but as bad as it makes me feel, I totally stop when I start feeling the slightest bit full.
After being banded, I had to take it easy on the items that contain a lot of citric acid such as Orange juice, V8, propell, etc....they upset my stomach and still do to a certain degree. A lot of reflux problems are caused by over production of stomach acid, and since you are just out from surgery, this may be your problem...I had the same thing happen and if I go too long between meals, I still have that issue.
Ask for some nexium from your doctor...or for the cheaper route try the Sam's club or walmart version of Zantac. Good luck!