I had unprotected sex, my periods starts on 4th day of the month and ended 8th. I had Intercourse on 11th to which I wasn't even intimated that much.maybe I wasn't ovulating at the time and the chances of sperm getting inside was very less. And I'm not even sure if it did cause the chances are very low.( I had levonorgestrel within 7 hours)and the pill worked and cleaned my blood). And there any chances of me getting pregnant? Id yes how to prevent that?