Help! Sex with condom & period irregularity?

So some of this may be a TMI but I’m really looking for advice here. My last period was around the 25th ish of December, and Im still waiting on it. Mind you, my period is very irregular and has either taken a long time or come twice within the span of a week. It was my second time ever having sex on January 11th, and a condom was used. We looked at the condom afterwords and all seemed to be okay, everything was contained. (he came) My period hasn’t come yet and I’ve been stressing like crazy these past few weeks over a lot which may contribute to the tardiness. Should I be really worried? Just in case on Friday I’m going to take a test at a friends house. I’m still in high school and worried out of my mind.