Period and stress

Okay, so I have been stressing a lot and I’m supposed to start my period sometime today. Idk why I’m so worried about it because I know for a fact I’m not pregnant. My boyfriend and I only got to see each other for a week due to a long distance relationship and when it comes to sex he always pulled out WAAAAAAYYYY before he came. I have been stressing a lot due to school and I’m worried that that is going to impact my period. It normally starts around noon on thursdays so I’m trying not to worry. Should I worry?