Hi Doc. I'm 36yrs Old, 1.7m Tall & 89kg. My

Hi Doc. I'm 36yrs old, 1.7m tall & 89kg. My last menstrual cycle was 25th August and was for 5 days. I had unprotected sex on the night of 1st September. I took the first Postinor 2 pill 11 hrs after (10am on 2nd Sept) and the second dose 18 hours after the first (5am on the 3rd Sept). Is this effective? Do i need to repeat this dosage? What else can i do asides hope i'm not pregnant? Thanks