This is not a pregnancy question but possible conception before birthcontrol? took it two days and light prd?

no this is NOT AN AM I PREGNANT QUESTION...let me rephrase the question. i was not taking the pill... i ve been feeling sick yes...if i start the pill but am uncertain if i am pregnant, if i decided to stop 2 days after starting the pill because of being unsure, if iw as pregnant would the pill still cause me to get a little period since i got off the pill/.....