Birth control/period

Hi I've just started birth control and took my tablets at the same time for the 21 days I was meant too and now I'm on my 7 day break and I'm onto my 3rd day and still haven't got any bleeding, I did have sex but used condoms bar once when he just pulled out. But I did get a lot of irregular bleeding during the 21 days of taking the bill. What do I do?