Becaue no form of birth control is 100% effective yes there is a chance you are pregnant however I highly doubt it. Women have been known to get pregnant while on birth control however you say you have started your period which is a good sign. You could always take a test to be sure but your moodyness and sleepyness could be attributed to many other things.

I appriciate your help, and I will let you know as soon as I find out.