I started taking birth control on Wednesday and its now saturday, i took a plan b pill just in case because when my bf and i had sex my pill wasnt activly protecting me. i dont know if i should expect a period soon? my birth control is supposed to push it off for another 3 weeks but because of the plan b pill i dont know if that makes it come early.  I know that birth control makes your periods lighter and shorter so im hoping someone can tell me if that is effective by just taking birth control 3 times, and if i get an early period from plan b if that will also be light?