whats happening?

iv been on Yasmin for several months now. but last month i started bleeding before the week i was due to stop taking the pill for my week off. because im anemic at the moment i decided to keep taking the pill through my break week as i didn't want to be bleeding for 2 weeks. then this month when i had my week off i didn't get any bleeding at all, nothing happened. this is really strange as normally im fine and its not like iv only just started taking it or anything. i don't think its ever happened before where i just haven't bled at all. what do u think?