Could I be pregnant? Please help.

So I'm on birth control. On October 10, I was late from my pill by 30-45min because I was out and forgot to bring it. I have taken it on time all other times. On October 12, I had unprotected sex with my boyfriend and he came inside me. Today is October 20, my period is supposed to start today but I haven't gotten it (yet) is there a possibility I could be pregnant even if it's only be a week?