In Need Of Advice

So, me and a guy have been sexually active for a little over a month now, and we don't use condoms, and i'm not on birth control. He also doesn't "finish" in me. I was worried that I was going to miss my period, because i was normally early than the time my app says im supposed to start. However, i was about a day or two late, but still started. I was stressed out because of school & the fear of being pregnant.

The beginning of my period was normal, like my other periods have always been, however I'm on day 4 and I think it has ended. This is only freaking me out because my periods normally last 5-7 days, and when doing research I found out that spotting was a sign of pregnancy.

I'm not sure if i'm just scaring myself, or if there is anything i could do, but i would really appreciate your advice ❤️ thank you