my boyfriend and i had unprotected sex a month ago. it was a few days before my AF was due. when AF was due, i had REALLY light bleeding (looked like implantation bleeding) which later turned into a medium flow with LOTS of clots. The bleeding never got as heavy as my normal period, but I read that implantation bleeding cannot have lots, so that led me to believe it may have been a REALLY early miscarriage. Now, AF is four days late and i'm beginning to worry. I had a negative pregnancy test after the abnormal bleeding last month. But maybe it was too early to detect even tho it was past my AF time?? Do you think i could be pregnant? Im 17 and definitely don't wanna be pregnant just yet.