when will the bleeding stop after taking postinor2?

It will stop when it feels like, havnt u notice the bleeding comes abnormally unlike our usual period. N the bleeding can continue three or four times in a month. It feels very weird girl n so uncomfortable but it will come normal again when the hormonal changes say over. I think it better we use condom instead of taking these contraceptives ,it may cause harm to us someday

Can bleeding occur a few days after using postinor2? How to know if the postinor2 worked?