Idk just stressing??

So ljs needed to rant or smth. , I'm 15. Me and my of had un protected sex 4 days ago, he didn't cum in me or anything (Ik you can get pregnant off pre cum that's why I'm worried) my period is supposed to start today but l've been so stressed about this because I'm so scared I might be pregnant that I'm afraid I'lI delay my period jus by being stressed bc I do that sometimes. So idk what to do. I've been freaking out and just hoping for the best. I was in my luteal phase, and lk that's like the lowest chance of me getting pregnant. from what I can find it's only a 4 out of 100 percent chance I get pregnant right now. But it's still possible. So I don't know. I don't think I am pregnant I am having normal period symptoms but my period is now a day late, and lk most pregnancy symptoms don't start until at least a week, maybe I'm just being super paranoid?