I Had Unprotected Sex And My Partner Ejaculated In Me.

I had unprotected sex and my partner ejaculated in me. I started my period the next morning, but it was about 3 days early (I'm usually very regular and on time) but seemed to be starting normally. Within hours of starting my period I took the Take Action pill about 15 hours after the incident. Then my period was super light and barely lasted the rest of the day. I'm having cramps and bloating. Could that have been implantation bleeding? Or could the pill stopped my period?