Hello, You should take i-pill as soon as possible and not later than 72 hours. The sooner you take i-pill, the more effective it is. i-pill is 95% effective within 24 hours of unprotected sex, 85% between 25-48 hours and 58% if taken between 49-72 hours.Ipills also alters regularity of cycle . So it could be pregnancy or pills effect. Do urine
pregnancy test at home . if it comes positive its pregnancy .