Which one are you taking? The combined pill? That can make you feel low and if you have depression can make it worse.
You sound like your a strong person? If you want to... stick it out for 3 months and give them chance to settle down, otherwise I'd talk to your doc and ask for a different birth control.
Cerazette (progesterone only pill) has helped calm my mood swings more than anything, but it's rare they give it out

Anyway, good luck hope your feeling better soon

-molly-