Can a higher dosage of Junel cause a late period?

I have been on birthcontrol for over 8 months now and have been recently switched to a higher dosage. This is my second month on this dosage and my period came late the first time and I am late for the second time. I was wondering if this has to do with the increase in hormones is messing my body cycle up. I dont think there is any possiblitly i could be pregnant because i always use a condom along with the birthcontrol pills. Please help give me an explanation as to why this has been occuring.