Is It Normal For Periods To Be Delayed After Taking Postinor-2?

i had sex with my boyfriend and took postinor 2,i took the two pills at once then after two weeks we had sex again and i took the same dosage of pills and uptil now i am yet to see my period,am i safe?i am 24 years old,i am 4 foot and 5 inches tall,my weight is 79,i want to ask a doctor online