I had unprotected sex and got my period shortly after. Is there still any chance that I’m pregnant?

If you got your regular period in accordance to your period calculator this would indicate that you’re not pregnant. If you noticed bleeding some time after unprotected sex and not on the days when your regular period should appear then this could be implantation bleeding. In that case it could be that you’re pregnant and we’d recommend that you take a pregnancy test.
You can read this post to learn more about how to recognize the difference between a period and implantation bleeding.