I have had blood in my urine just like you explained for years. I always had pelvic pain as well. About 3 years ago I was diag with Interstitial Cysitis (IC). It's a bladder disease and will cause blood in the urine. Once I was diagnosed other things made sense. I felt pains that I had no idea were my bladder all those years. My OBGYN finally sent me to a Urologist and they were able to make the diag fairly quickly.