Severe Abdomen Pain. What's the reason?

Hi, I'm suffering from abdominal pain from last so many years(approx 8-9) I didn't even remember. I went to numerous Physicians and Gastro Doctors, done ultrasound so many times,but results are always clear. This pain sometimes becomes so severe that I even can't able to stand. My Mom has taken me to Hakim in our village " he rubbed my stomach with some oil ".It has given me relief for some time but he said I have some blood clot or tangled blood vessels because of which this pain arises. I felt this severe pain more in middle of abdomen and in the left side of my body. It's involves whole area below my chest and above my waist.In case I go to office early with empty stomach,this abdomen Pain becomes breath taking. Can you suggest me what could be the exact reason of this pain and how can I cure it?? It's my pancreas,liver or stomach .... What's the reason?