Burning pain and low grade fever ?

Every once in awhile I'll have a few beers (4), the next day I wake up with a burning pain in my intestines and I'll run a low grade fever for a day 99.8. I have been to see two GI doctors and have had a Endoscopy and a colonoscopy done. The Endoscopy showed that I had Barrett's Esopahgus, GERDs, acid reflux, a hiatal hernia. The GI doctor put me Nexium 40mg twice a day and it really helps, my PCP keeps changing my Nexium to once a day, which makes my GI doctor mad. My PCP isn't even a doctor, active nurse. This has been going on for months now. Anyway, the colonoscopy was clean, but my PCP sent me for a stomach scan with contrast, which she said, showed I have Diverticulitis. My GI doctor says, I don't. My GI doctor is is the city, my PCP is out in the country side. Alls I want to know is what could be causing these burning pains and low grade fever when I have acouple of beers !