What Are The Chances Of Pregnancy After Taking Ipills?

hi doctor.i had to have my periods on 6th.but until 8th february i didnt get periods.due to some comittment i postponed it by using primolut for two days.during that time i had an unprotected sex.after 25 hours i took prostinor 2.and the next tablet after exactly 12 hours after that.still im not having my periods.this is 13.is this something to worry about?