possibly pregnant😫

so on sat night me n my bf shagged n my period is late by 2-3 days now, we didn’t use any protection n i don’t think he finished inside me, i’m still scared asf that i’m pregnant, i was meant to be starting the pill but i can’t until i start my period but i’ve not come on :(, what should i do, not close enough to my mum to talk about it with her any advice please x