Is Pregnancy Possible Despite Taking Emergency Contraceptive Pill Within 48 Hours?

Hello Dr.can u plz tell me about pregnancy actually me n my husband had sex on 11 th jan without any protection but within 48 hr I take pills n in 14th Jan my periods will be started in a proper way very high flow n very painful but after 1st periods my mensuration cycle is not coming what s the reason Dr.n can u plz tell me can I pregnant or not ? N after 11th Jan we had no sex plz tell me after periods how many chances to get pregnant