Very scared and confused....

Hi everyone. I need some advice. So my boyfriend and I have been dating for a year and a half, and we've been through a lot together. We are still pretty young, so we just decided to take it to the next level about a month or two ago. My period was a few days late, and yes, it could have been from stress or the fact that I get ovarian cysts, but I got very terrified. When I finally got my period I was over joyed, but I just read in another users post that you can still bleed as if you're on your period if you are pregnant. Now I don't know what to think! It could be nothing, but I can't help but worry and worry and worry!!