High And Fluctuating BP, Severe Headaches, Vomiting, Inflammation Of Stomach. Low Potassium. Suggest?

for over a month my BP has been very high & fluctuating. 3 wks ago I started having stomach pains, thought I had the flu. Last week I was taken to the ER via ambulance due to high BP (206/166), severe headache, and vomiting what appeared to be coffee grounds. The hospital said I had low potassium and slight inflammation in my stomach and pancreas . They treated me for the issues listed, brought my potassium up and sent me home. Since then my symptoms have continued and in some ways have gotten worse. I now have diarrea that often resembles coffee grounds, my stomach feels raw inside and there is a pain under my bottom left rib that feels like someone is stabbing me with a dull knife. oh, and my stomach is swollen slightly - I dont know what to do anymore as even drinking water makes the pain worse.