I have had some experience being late on the pill. Did you have a lot of stress this month? Maybe you forgot a pill or took it later than you should have? Any of these factors can make you period become late. Don't worry about it, I'm sure it's nothing. I would wait it out, and if you do not get your period after you have finished your inactive pills, call you doc and check with them. Good Luck! I'm sure it's nothing to worry about!