My partner and I have been having un protected sex. Tryimg to conceive. I started cramping 6 days after my ovulation day.( I track my periods and ovulation.) I also was very tired, moody, and urinating alot. I took 2 pregnancy test, 3 and 2 days before my period was due and they were both negative. The day before my period was due I went the restroom and was passing clots but not really bleeding much at all i am having bad cramping and backache. Today is my due date for my period and still the same things. Just clots, not bleeding much at all and still cramping, also my breast a very tender. I took another pregnancy test this morning and still negative. My periods have been normal for the past 3 months. I do have a history of endometriosis and ovarian cyst which I have had surgery for about 2 years ago. What could be going on with me? Any advice would be appreciated!