Late period or could I be pregnant...?

Okay I’m super scared and need help... I feel like my period late and I can’t remember when I had it last... I know it hasn’t been over two months since I last had it but I just don’t know if it’s just super late or if I’m pregnant.. I had unprotected sex with my boyfriend maybe 3 or 4 weeks ago (rough guess) but he pulled out. I know about the possibility of getting pregnant with pre-cum. I took a pregnancy test and it came back negative but I still don’t know if it was accurate... I just need some advice on what to do. I’m going to the doctor next week be just need some guidance and/or advice now to try to help calm my nerves until then... I’m super scared right now so any advice at all would be much appreciated