hi first of all good luck with surgery i am sure you will be fine. I did not experince the gas much at all, but i did when i had a c-section, the best thing is to walk..and drinkin hot black sugar fee tea..(you an make it devaf if they have you off caff at first) I had a post op migraine that was the worst part of the whole thing for me, but they gave me strong pain meds and it helped.
My advice would be go easy on yourself. I expected miracles from this..(in my head, i never told anyone) and it isnt..You will still have to diet and exercise and really watch what you eat...but you are going to feel sooo much better when the pounds start to come off.
I was banded in september, getting my second adjustment this tuesday..and have lost about 22 lbs..(but i am on some medication that makes my metabolism a bit slow ) Everyone is different!!!
Good luck with your surgery. Stay well.
Diane
N.J.