Please help?

Hai I'm 18 and really need some advice. Okay so some time after loosing my v-card my bf and I like 2-3 months later had sex like a few times in the day then like 4 days later I started some really heavy bleeding. The bleeding went on lasting for 2 weeks then trickled off and of course we were both on panic mode because of pregnancy but at the same time I knew it wasn't that because that's not a pregnancy symptom. He asked his mommy about it and she said it's probably from friction and me not being use to rough sex. So after it stopped a few weeks later I got my actual period. It changed the whole schedule of my period but it was still trackable. But as of my last one it came like a day late and as of right now it's 2 days. I have sex with protection of a condom because for us that's a must so I'm trying not to over think it dipping into pregnancy and I also never went to the doctor for any of this because one my mommy doesn't know that I'm sexually active and I'm personally not ready to let her know...Any advice please?