What Causes An Ongoing Pain In My Upper Right Quadrant?

Hi i have had ongoing pain in my upper right quadrant for almost 4 years now. It started when I 22 after about 2 years I had tests showing I had a hiatus hernia, gastritis and H.pylori. I am still in pain but have been told my hernia is too small to operate on and wouldn't cause me this much pain and have since had tests on gallbladder, bone scan, pancreas, x-rays, scans etc. The pain starts in my right side just under/behind my bottom rib and can spread round into my back. The pain usually lasted for weeks but comes and goes I get a full feeling really easily like there's not enough room in my stomach after a few mouthfuls my stomach grows in size extremely quickly looking like I'm about 6 months pregnant. Exercise aggravates this more. I also get bloating constipation diarrhea nausea. Recently I read about dyspepsia could this be a possibility for me? If not do you have any suggestions I really need some help, at times I feel as though I'm going crazy. I'm only 26, but feel much older as this seems dominates my life, mood and what I do. I am 5'6 and a little over 10 stones.