I missed my period 3x in arrow while on birth control pills. i checked to see if im pregnant but i'm not. can stress cause it?should i stop it?

Common issue: It's not uncommon to have lighter periods on the pill: even no periods! this is because the uterine lining doesn't build up the way it does when you aren't on the pill. The lining is what is shed, creating your period! less lining = less flow. As long as you are a girl scout about taking your pill, you are not likely to get pregnant - but you are right to do a pregnancy test to be sure.