I got stomach problems?

ok ive been having problems with my stomach since the being of june this year. i have pain in my stomach by my ribs and then itd shoot up in my chest. i have shortness of breathe every time it happens, i have lower back pains and my stomach never stops rumbling and i always wake up feeling nauseous. ive lost about 30 lbs from loss of appetite. ive been going in and out of hospitals from my attacks because itd only hurt for a couple hours. they can never find anything wrong with my. i took a crap load of blood test, i got a colonoscopy, stomach scope, and ultrasound. they found nothing. i was gonna do a cat scan but id figure they still wont find anything out. my doctor umes that my stomach just twitches or whatever so he gave me some pills and they never worked on me. im just really mad not knowing whats wrong with me because it comes and goes everyday. im sick of it