First Of All, Let Me Say That This Problem Has

First of all, let me say that this problem has been ongoing for close to four years. When this problem originated I had pain and an uncomfortable feeling( like a knot ) in my right side just below the rib cage and lower right abdomen. At that time I went to the ER, but they couldn't't find any problems. Since then, I've had several follow up visits with different doctors and have had several test run ,like an ultrasound and cat scan, but the cause of my pain hasn't been located. I was originally told I had a hernia, but test were unable to locate one. Now, four years later, I am still having problems and no one can tell me why. I don't have insurance and this has kept me from more aggressively pursuing an answer. It is now to the point where I have like an uncomfortable knot under my right rib cage all the time with low grade pain in lower right abdomen. I was wondering if you knew something that I could have my doctors check for. Thanks.