Well if you're having spotting obviously you should at least wear a pantyliner unless you want to get blood all over your underwear. As far as how heavy it is, that's going to vary for each person individually. Personally, in the year that I've been on birth control I've only ever had spotting once for a day and it was incredibly light and spotting is supposed to be more common with my birth control than with others, and especially within the first couple of packs. Really, you shouldn't worry about it.

Also, you most likely won't get "terrible mood swings" so you shouldn't worry too much about that.

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