Thanks for the additional information.
I think that you're just fine, at this point. Give it another day or two, and I bet that your period will start by then. Although some women are very, very regular, a little variation in cycle length/timing is not at all abnormal. So you should feel reassured.
If, within a few more days, you still haven't had your period, then you can give your gynecologist a call before you start your new pack. But I think by then you will have probably already started to menstruate. If not, however, then make the call.
But you should be just fine.
I hope this helps. Please let me know if you have any further questions - I'm more than happy to help.
Take care - Dr. Fay
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