What Causes Vomiting And Burning Sensation In Abdomen After Taking Zantac?

I am starting hormone treatments which include 3 different medications. When I was too start, I just stopped taking Lexapro and toprimate (used for migrains). I had severe withdrawals for a week. However, the last few months, I have been vomiting out of no where. It will come and go but the past 2 weeks have been excrutiating. I throw up multiple times a day now and my stomach is always feeling bad. I have done an ultra sound in my uterin region just a few weeks ago too. They found some rather large fibroid masses and some ruptured cysts but do not seem bothered with them at this point. Now, I just found out I was dropped off of my insurance and have to postpone more testing until it is figured out why I was dropped. In the meantime, I ve lost 7 pounds in less than 2 weeks because I cannot eat. I thought heartburn and took a zantac. within 20 minutes I was vomiting and had a burning in my abdomen and throat I have never felt before. I should also mention I had an appendectomy in November. Could the medications (which I only took one - for 4days - and not the others as I will have to do the process again when I get my insurance back anyway) be causing all this? At this point I am not taking anything for about 1 week. Im just very hungry and thirsty and eerything makes me sick. Any ideas?