@charlotte49,
I suspect you are experiencing premenstrual symptoms. If you haven't had your next period within about 10 days, then it is time to go see a doctor.
While there, ask their staff to give you some reading materials so you can be better informed about how birth control pills are supposed to be taken for maximum, uninterrupted protection.
Skipping pills for weeks at a time is just asking for trouble, both in pregnancy risk and the havoc the roller coaster of hormones will do to your body.