My last period was Sept 24-28. According to my calculations my ovulation day was Oct 8th, me and my partner had unprotected sex and he came inside. On the 12th I had a awful headache , the next morning I woke up to some spotting, backache , lowe abdomen pain and soreness. The bleeding was on and off only when i wiped, not like a normal period, i noticed my aerolas are alot bigger and puffy. I have very little brown discharge now. On the 16th i went to the ER because of the pain around my ovaries, I also noticed some twitching and soreness, like I worked out the night prior. They did a pelvic exam, urine and blood test. all negative and normal. If i am not pregnant , what could it be? and how accurate is a blood test after 8 days past ovulation?