Implantation bleeding?

I am 16 dpo, and when I wipe I get this, I just started a combination birth control pill this month and my period is due in a few days, is this implantation bleeding or just spotting from the birth control? I had unprotected sex with him pulling out except once, and it was after the 7 days your supposed to wait. I had sex once before the 7 days but took a plan B  the next day, please help!!!!