Possible??!😞😞

So i had sex with my SO on April 28, May 2, May 3, and last night. So 2 times last week, and 2 times this week. I started bleeding last night. I think its so weird how my SO said there was a bit brownish stuff on him after we finished. just a little tinny bit. But when i went to go pee afterwards, there wsnt anything after i wiped or anything! Till i got home and went to the bathroom and wiped again and saw some light bleeding.. is it possible for it to be implantation bleeding? Im SO ANXIOUS to know! How many days after implantation could i test to get a BFP??? Help pleaseee😞!!

Ive also been feeling with this crazy headache, sore nipples, moody and a little nauseous. (Enough to handle and not vomit)