Im 48 years old and can take a hell; of a lot of pain but?

lately i have gotten excruciating pain in my solar plex ares and sometimes it feels like my back has been broke in half. the pain last about 4 to 6 hours. its so bad my palms sweat and i get real shaky. Ive been to the hospital but they keep thinking its my heart and miss diagnose me. like i said I can take a lot of pain but this just doubles me over and makes me want to die just to get rid of the pain. I was thinking ulcer but I don't know. has anyone else been there and done this if so you know how bad this pain is. nothing but time gets rid of it please help if you can I cant take it anymore