Sex before period.

Me and my boyfriend had protected sex the day I was supposed to start my period, (according to the <a href="https://play.google.com/store/apps/details?id=com.glow.android.eve">Eve</a> app.) He didn't even cum or pre cum inside the condom. I have no signs of being pregnant what so ever, but my period is late by almost a week. This week has been really stressful for me, because we're both thinking of the worst. I've read that worrying and being stressed about it only makes it worse. Any advice? I honesty just need some comfort here. 😭