Hi there -
i don't know that taking pills now will prevent your impending period. But for future reference, if you take all active pills (and skip the "period" pills in the last week of the pack), you won't get a period. It is safe to do this as long as you wish! Check out noperiod.Com if you want to learn a bunch more about it. I've been doing this for several months and it's great!

The skipping period only works when you are regularly using the pill.

That site has great info about skipping periods.

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No, there is no danger. Hormonal birth control simply stops ovulation, the period you receive is only because you stop the pill, it is not a real period at all.

Female gyn students have used back to back birth control for years to stop their periods on long rotations, it became mainstream and popular recently though.