Feeling Light Headed, Stomach Hurts And Tiredness. Took Anxiety Pills. Diagnosed With Gastric Ulcer Disease. What Should I Do?

Hi, I went to the ER 3 times in the past 3 days, the first time they did not diagnose me with anything and said it was nothing more than anxiety and its in my head. I went the next day because of the same symptoms. light headed, stomach hurts, I feel tired but cant sleep. but then i'd randomly fall asleep during the day for 8 hours and be up the rest of the night, they gave me axiety pills and discharged me AGAIN. It persisted onto the next day and I couldn't bear it, I felt like I was going to faint. When I went back the doctor diagnosed me with gastric ulcer disease or something along the lines of that.. I didn't want to be discharged because I knew it would happen again. Now here I am with what seems to be a bad headache and the bad stomache pains. They did blood tests and EKGs and say everything is in my head at this point. But they still discharge me when I want to be cared for. What can I do? My name is John.