Back pain/gas? 2 yrs post op

For the last 3-6 mths I have been getting these horrible pains in my middle right side of back and I am thinking it is gas.  I get them after I eat and it seems that it may be after bread or crackers (I try not them and rarely do).  Could it just be gas?  I also have been bad and started drinking 1 diet coke a day again and am wondering if it is that instead of the bread.  I will be 2 yrs post op at the end of July so this isn't happening to a newbie.

I would avoid the bread and crackers and also the diet coke and see if it goes away.  I would think that if it just started after you added those things that it may go away if you take them away.