Passing tissue again while in period. TMI!!!

Im passing some tissue again while on my period. Once again. Er doctors told me they didn't see anything so they don't believe me. This was a month ago. I was late for my period. Had two positive pregnancy test, negative blood test. They have not check for anything going on. Infact the er doctor told me it was just pms for the stomach pain. I have some pain under my ribs. On my left side. I will admit most times having sex hurts. Wearing a tampon most times even hurts. I had a baby 9 months ago. So I figured it was just normal for this to happen. Now I'm thinking it's not normal anymore. My temp is usually in the 97 range. It's been in the 99 range . Any ladies experience this? And what was the outcome?