Irregular period from pill/pregnancy

I've been on birth control for years now and having a period is not always guaranteed. Sometimes it worries me. Like I had sex a little over a month ago and I've had a lot of early pregnancy symptoms, with a friend even pointing it out. But my period still hasn't come, and I don't know if it's because of the birth control or actual pregnancy. It honestly would be nice to have it as a sign each month so I definitely knew.