When fertile sperm contained in semen deposited in vagina ( during fertile period ) reaches to ovum n fertilizes it later leading to pregnancy
You had sex during safe period (and probably no penile insertion into vagina occured as not real sex ) so chances of pregnancy is less. One can have emergency contraception
to protect from unwanted pregnancy within 72 hours of sexual contact .Do UPT if you don't get your menstruation
even 1week later than your expected date of menstruation to confirm .
Hope this ll help
Thanks n regards