Upper left rib cage quardrant/abominal pain

I am 32 yrs old and suffering from upper left rib cage quardrant/abominal pain for 2 months. The pain is not related to what I eat and does not feel on phyical examination. But the dull pain comes/intensity increases by sitting or laying back. I dont feel the pain when I walk or do exercise. Have been visiting GI for 2 months and performed following tests:
Endoscopy - Normal - Found h pylori bacteria and mild gastritis. Having been taking Nexium for 2 months. No changes in pain. Taking medication Prevpac for h pylori - taking about 10 days.
Colonscopy - Normal
CT scan of abdomen/pelvic - Normal
CT scan Enterography - Normal - But found Mesenteric panniculitis. Doc said Mesenteric panniculitis is minor and will disappear by itself and nothing to do with upper left abdominal pain.
CT scan examination of lower chest/chest xray - normal
blood test - normal
bowel movement: Normal and never had problem.
Medication taken so far: Prevpac, Nexium and antiacid. Medication for muscle pain.
History: I get upper left quardrant pain on taking some food like potato/peanuts. But disappears on taking antiacid and have stopped these problematic foods for 2 months
The doc suggested once I complete Prevpac and he is going to put me on IBS/Stress mediciation. I dont feel stress and my bowel movement is normal. I am humorous and easy going person. Never had problem of stress.
Has anyone got gastritis whose gets pain by sitting/laying back?
Has anyone got IBS/Stress who gets pain by sitting/laying back?
I am not able to drive car because of pain and I need to sit infront of computer for job. This is driving me nuts as Doc does not have answer and not recommending further any tests.

Please advice. Has anyone suffered symptoms like mine?

[crambone]

i have similar issues,and they too are worsen with sitting and laying down....i think it is muscular/skeletal,,,and not to do with stress exct.
possible ibs/gasteritis syptom (symptom),,,but also gullbladder (gallbladder)/pancreas symptom too.
i have has about everything checked out from gallbladder to diabetes to pancreas,,everything,and they find nothing,,,i still say possible nerve/muscular/skeletal issue.

[Mb2009]

My sincere thanks for responding to my question. I was desperately looking for answer. But gallbladder and pancreas were fine in ct scan? Do still further test required?
what did you do for your pain? How did it disappear?

[Mb2009]

Also I forgot to test you Blood Liver function test was - Normal
Blood test for pancreases ( amylase and lipase) - normal
CT scan of pancrease/gallbladder - normal
Do you still think test further test for gallbladder/pancrease need to be done?