(( VaginaPagina ))

Ok, let's see if I can explain this in a good way, haha. Withdrawl bleeding is something that happens when a large amount of synthetic hormones are introduced into your system and then are not replaced. When women on hormonal birth control (pills, patches, rings) are having their "period" it's not really a "real" period, because the hormones stop ovulation which pretty much means you have no menstrual cycle at all. The 28-day packs are just for a sense of normalcy, because most people need to have their "period" every month to make sure they aren't pregnant/every thing is working OK. The "period" that women experience during hormonal birth control (and in your case of taking EC), is just their bodies reacting in a way to let them know that all the synthetic hormones are out of the body.

I hope that made sense! If I'm incorrect about something, someome please let me know! This was just how my GYN explained it to me :]