Had unprotected sex but took the morning pill the day after. 5 days later i had heavy bleeding that lasted 3-4 (during ovulation) what was it?

Hormone effects: Emergency contraception pills are a one-time bigger dose of hormones... meaning the effects are temporary but are disruptive to the normal cycling of a woman's hormones. That means there may be some vaginal bleeding irregularly for 1 or even 2 cycles, because vaginal bleeding can come from changes in the lining of the uterus related to hormonal level changes in the body.