So, "breakthrough bleeding" is a term that just means any unexpected or unexplained bleeding while using oral contraceptives. For sure, that's what's happening here, because this is bleeding you aren't expecting. Clearly, this isn't an issue about pregnancy, because you used two methods -- albeit, it might be your pill wasn't as effective as it could be, but still -- and it also seems most likely this is happening because you stopped and restarted your pill or because you're simply having your period. That is what most often happens when people don't take the pill for a week.
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