sharp pains in stomach...quelled by drinks?

This year I have had several episodes of sharp pains in my stomach. These episodes usually are in the early morning (5:00 a.m. - 8:00 a.m.) or later at night (10:00 p.m. - Midnight). Usually after several hours of the pain, it recedes, but today, during the episode, I took a drink of soda, and a lot of the pain stopped.

Are there any ideas what this could be?

several things that I think may be attributed:

I am 220 lbs.
I tested negative for diabetes two months ago.
Yesterday there was a gathering, and I ate quite a lot more food than I usually do.
I have had 2 surgeries around my colon/small intestine/appendix area around 10 years ago.
When I lied down during the episode, the area around my left kidney hurt as well

any help would be quite appreciated.

Thanks