Implantation Bleeding? or Early Period Bleeding?

Had unprotected sex with my boyfriend of 2 years, 2 days ago and my boyfriend ejaculated inside of me. Could this be implantation bleeding? 2 days would be too early I assume. But we also had unprotected sex a week ago and then, he ejaculated in me too. Is this implantation or is it early period blood that just hasn't completely started yet? Can someone let me know? Thanks