Hi Doctor, I Am 25 Year Girl And My Last

Hi doctor, i am 25 year girl and my last Menstruation start around august 17 and i had unprotected sex with my boy friend in September 05. So after sex i had POSTINOR 2. ( first one with in 2 hours and 2nd one within 12 hours ) so today, 24 th september and i still didn't have periods. but previous days i had some pain in my stomach like cramping. can you please explan is this normal or am i pregnant ? thank you.