I could be pancreatitis, but a simple blood test should make that diagnosis clear to your doctor.
I have had upper left quadrant burning for over a year now. I have had every scan and blood test my GI doc could think of and everything comes up normal. I have also tried several meds for IBS (Bentyl is one I can remember off the top of my head) but nothing has helped.
I do hope you have more success in finding out what is causing your pain than I have had.