Help!!

So i'm in college and i was having casual sex with this guy and we haven't talked in awhile so i hit him up, he lives on campus and i don't btw so i come to his dorm and we're making out and i give him head then he cums so he goes to the bathroom and switches places w his friend(we were in the dark) i figured it out bc of the voice so i grabbed my stuff and left what do i do!! i'm so distraught