OK so I'm 16, I had sex twice in the one night, with no condom (I know stupid). That was three days before I was due for my period but I am now four days overdue... I have done a home pregnancy test two days ago but amm worried I could still be pregnant
??

ANY time there is penile insertion there is the risk of pregnancy.You can minimize the risk, but not eliminate it.

So, yes, since you had sex, you could be pregnant. You will have to wait until about 2 weeks after your period due date to take a test.

And if being pregnant at 16 worries you, then why are you taking the risk. Keep your pants on!