Scared I might be pregnant !

Hey Girls. So here’s the scoop..my average cycle is 27 days. I had unprotected sex on this past Thursday Sept 12, and my period is supposed to come Sept 28 and ends around the 3rd-4th. I’m like really scared. He didn’t cum at all, but I understand having unprotected sex any time is a risk, especially around the days of my ovulation (if I’m right mines was about this time)...what should I do???