someone help

Bryanna
I just ended my period the 10th, now I continuously am spotting every day and I'm supposed to get my period the 22nd. 
I missed my birth control once.. the day I drove from college back home to see my boyfriend... and we had sex unprotected. So I'm confused. I don't want to be bashed but I'm just confused as to why I'm constantly spotting when I'm off my period and I only missed my bc once..