Pregnant?

So I had sex last month for the first time during my period about 3 days after. We used a condom both times, no holes in it (for sure) and he didn't even fully finish. However AF was due two days ago (though I've never had regular periods anyways). Last week I started cramping, and all the signs of AF has been there for about a week (which is normal for me) but still no period! I'm 17, and this is freaking me out beyond belief. My CP is all over the place (some days it's low, some it's high some it's medium but it's always open-feeling). I'm absolutely terrified, especially since that's when I lost my virginity and idk. Does it sound like I could be pregnant?