Help please.

Hello. So 2 weeks ago me and my boyfriend had unprotected sex however he pulled over but im not sure if some stayed in or not. That night i had gotten food poisoning and after that i experience pain in my back and down there. Headaches, fatigue, and some bloating has accrued. Oh and acne with mood swings. I hadnt vommit nor had tender breasts and eve. Said i was suppose have my period the 17th but im not sure if im late or having irregular periods. Im only 18 and really worry. Thanks..

Also. Im not on any birth control or meds