Opinions please! Birth control and pregnancy

If I were to be pregnant (and not realize it) while taking birth control, would I still have the withdrawal bleeding when I get to the placebo pills? trying to figure out the best time to take a pregnancy test. took one the other day and said negative but I don't trust it.. but I feel like even if I were pregnant, if I stop taking the birth control during the placebo week, I'd have the withdrawal bleeding anyway. so I can never tell if I'm actually pregnant or not. 😬

What do you guys think? I've tried to research it but can't clarify anything about the withdrawal bleeding still occuring if I were to be pregnant without knowing.