This Is A GI Question: I Have Been Experiencing ,intermittently,

This is a GI question: I have been experiencing ,intermittently, what looked like biliary attacks. However, since a very severe attack at the end of July that lasted for 3 hours at a 10/10 on the pain scale, I have not been back to normal and unable to eat solid food since mid-august without being in excrutiating postprandial pain. I had an ultrasound that was exactly the same as it was in 2012 when all this started: normal, no gallbladder, liver or pancreas problems noted, no gallstones and only two small polyps that have not changed in 6 years. Symtoms now mimic more those of a duodenal ulcer but the barrium swallow was also normal. The pain is localized in the RUQ mainly in the back and occasionally I do have epigastric pain in particular after few hours in crisis. Two GPs prescribed PPIs which made my symptoms worsed and had to stop due to severe headaches. Cytotec was also tried and not tolerated. Only thing that keeps the pain away is a liquid diet. Use of Pepto Bismol PRN has helped when epigastric pain is present...Feeling quite helpless and not very well supported by my physician because all my lab work and tests are normal I feel that I am looked at as it is in my head. I have a busy and very well fullfilled life, I could live without this pain! Any idea of what could be a possible cause for these unexplained symptoms?