Could I be pregnant?

I’m 11 months post partum and have been on the mini pill since my six week appointment. I have not been taking the pill faithfully for the last month maybe a month and a half. I stopped taking it completely on the 10th of this month, was expecting my period on the 13th, but who knows how my cycle got thrown off. I had sex on the 11th the 12th the 13th and the 16th. Still no period and now I’m having random nausea. Could I be pregnant?