am i pregnant?

hey guys i don't ever post on here and i'm not even sure how this works or if this will even post but i need advice. i had unprotected sex (yes i know i'm stupid and i regret it) around the 20th of january and rightnow i am having the worst abdominal pain of my life only on the left side and in one spot. i have been working out this past week doing ab exercises so maybe that's it but idk.. i feel like it's more than just pulling something. i'm supposed to start my period in 3 days but these are not period cramps. do any of you know what's going on?