I had unprotected sex almost two weeks ago. It happened about a week before I was supposed to get my period. I ended up getting my period 4 days late. I didn't know if since It still hasn't been two weeks, and I had my period does that make me not pregnant? Or is there a chance I actually could be pregnant?

Usually, 98% of the time getting your period is the clearest indicator that you are definitely NOT pregnant. There are only a few crazy stories where women were pregnant and still got their period, but the chances of that are highly unlikely.