When Should Contraceptive Pills Be Taken?

Hello Doctor... my period starting date is on 14th apr. i had unprotected sex with my bf on 10th and 11th apr. we thought its safe before one week the period. so dint take any contraceptive pills.
is there possibility of pregnancy? will unwanted 72 work if i take it today i.e 13th apr after noon. if it wont work what is the other option to avoid pregancy