OK, a few weeks ago I got drunk and hooked back up with my ex. And well we had unprotected sex. Then 3 days later I start my period, but it was a week early. Well I was just wondering if there was a chance that I could still be pregnant or should I just no worry about it.

Are you sure it was your period and not spotting?
If it was your period, its highly unlikely you'r pregnant.
If it was spotting you should take a pregnancy test