My answer is based upon memories of many many years ago but those years were so very bad I'll never really forget it.At the time I had Endrometriosis, I also had Ulcerative Colitis so I was pretty much a mess. I think there is still no blood test for either except for ruling all other conditions out and diagnosing only by viewing during invasive procedures. In my case; UC by colonoscopy when bad ulcers could be viewed and Endo by surgery for a huge mass removal that turned out to be an ovarian chocolate cyst and the misplaced cells could be viewed elsewhere. The pain was very bad much of the month... but, I must also tell you that ...the diarrhea worsened and abdominal/back pain intensified and was constant during the 2+weeks time-frame surrounding my 10days-long periods.Once, when I was hospitalized for 2 months for the UC, my periods hiked up the pain level so bad they had to give me narcotics by injection. When at home, I tried every method possible ie heat, positions, rest, etc, to save my pain med Rx for when I needed to be social (teens-20s). Just an awful nightmare. The hemorrhaging made me anemic. I missed school or at least PE class, everything social, then later, work -to the point that I got fired for being too sick and hospitalized too much to be counted upon. It was a hard road. After multiple surgeries either removing parts inside me damaged from it or scraping it off places like my bladder, and living in horrible pain which had grown to 3 weeks/mo (not to mention the UC), I finally agreed to the full hysterectomy at 27. The ovaries are the culprits so my only 1/4 left of one side and it's not so great remaining tube, were removed along with my bad uterus (by then adematosis too so could never have held a baby by then). It was a miracle.... within a year, I could see that having pain from only one condition was a lot easier. Within 3yrs we had 2 beautiful baby daughters (17mo difference) by adoption who, as adults, remain utterly devoted to us. Now, though UC's in remission(after 20yrs of it), I have severe IBS-D, then 8yrs ago Rheumatoid Arthritis started up so I'm back to 2 conditions of pain. Not fair. Anyway, that's my experience.I'm so sorry you are suffering from the 2 painful conditions. ......btw... like back then, I find my dog to be the best therapy of all! Cathy