PLEASE HELP!

On the 10th of december I had unprotected sex and immediately took plan B. Everything was ok, then my “period” came on the 17th and since then I’ve had it. I’ve had it for 10 days now, is this normal? Usually my period lasts 6 days max. This is no pregnancy right? “Implantation bleeding”, because it has been a lot of days.

Please help educate this girl!😔