Sex then period

Okay guys.. not sure if this is a stupid question or not.. but the other night my SO and i were having sex, but pretty quick into it i made us stop because i got nervous about not using a condom. The very next day i started my period. But now i feel very nauseous (not the same as my period..) do i have a reason to freak out? He didnt finish but i feel like an ignorant

Middle schooler 😂😂😂