thank you for using healthcare magic,
well if you have missed pill for more than 12 hours it might affect effectiveness of pill.. now continue pill everyday at same time.. use back up method like condom..chances of pregnancy
with withdrawl is very high.. condom will be better option then withdrawl..
if you dont get your next period take home pregnancy test after week or you can take more confirmatory test like beta hcg
level or ultrasound
hope this helps you..