What Causes Pain In Pelvic Area?

I've been in and out of hospitals since march, ive had debilitating pain in my pelvic area. when i'm in pain it lasts from 4-9 hours sometimes more, ive had xrays ultra sounds (internal ultrasounds too) every test under the sun. Nothing has came back with any answers, except that i once had a cyst, which obviously i can tell it wasn't the cyst. it's almost every day i'm in pain i feel like when i try to stand up my insides are ripping apart, theres a tugging or pulling sensation whenever i move. I was diagnosed with IBS but they came to terms that i just had "IBS-like symptoms" and didn't actually have it. Well now i'm stuck because I've had every test including gastrointestinal testing as well. The only two thinsg i haven't been checked for yet are Endometriosis and IC. which i'm afraid if i try to go they're goign to tell me it's not either of those. I do have symptoms of endo, i've had these symptoms since i was young.