I had unprotected sex on February 28th and March 1st, the day before and the first day of my period, and both times he ejaculated inside of me. I know it's hardly possible to get pregnant in a case like that. But I've always been irregular and I have no idea when I possibly could have ovulated. 2 days ago I started spotting brown. It lasted for two days. I've heard of implantation bleeding and this bleeding resembled that. But I'm not sure it's even possible for me to be pregnant since its been so long since I had intercourse. I took two pregnancy tests when the spotting first started and both were negative. I hope I don't sound super ignorant. Any help or insight into this situation would be much appreciated! Thanks!