I Have Been Having Some Stomach Issue's For The Past

I have been having some stomach issue's for the past three years. They remove my Gall Bladder in January of 2013, I had lost about 40 pounds in about 6 month's. The first time in December of 2012, they put the stomach issue's on hold. They found out that my heart was in Afib. Then still having trouble eating and keeping it down or in for any length of time, it was going up or out the bottom, I went back in the hospital for another week. That's when they said that I had a gall stone the size of a walnut, then removed the gall bladder. I was in for a week, and then had to go back in two weeks later for the same problem with my stomach issue's. I was admitted again for another week, and told that I had Pancreatitis. They gave me some medicine that did not work, but I had talked to an old customer and he had a person in his office that her son had something almost just like mine. She gave me some sample's of Domperidone, that was prescrided to her son that helped me, after about a week of taking them. I got with my doctor and he wrote me a prescrition for them and I had to fill it in Canada, where they make it still. It had helped up until the end of last year and I started having the same issue again. In Febuary, the doctor ordered an ultrsound of my abdomine and they found what looked like a stone in my bile duct. They wanted an MRI, but I didn't have the money for that. I'm on SSDI for Myasthenia Gravis, and I just couln't afford the MRI and buy my expensive medicine for my MG. If I don't get that medicine, I quit breathing. So it was a no brainer. Oh yeah, I've had five previous MI's and a mild stroke. The last MI was in 2005. Help please. I don't know if the back issue is related, but when I was diagnosed with the MG, they found a malignat tumor on my Thymus gland and part of my left diphram, and had to remove the Thymus and part of the left diaphram and now the left lung dosen't work, since 10/01/1993. I had 35 treatments of radiation therapy, so far each year I get test for cancer, I've been clear. Last blood test was the middle of Feburary.