Get a pregnancy test if/when you miss a period.

You can absolutely get pregnant on the pill. Especially if you've only been on it "like not even a month." .I was taking mine religiously for years but got pregnant 2x on bcp's when .I was also on antibiotics for extended periods of time.

When you miss your period, take a test or get a blood test from your ob.

If you've taken your pill every day at around the same time, you shouldn't be pregnant. Like queen bee said, it does happen, but only if you miss a pill here and there or if you're taking antibiotics, because some of them decrease the effectiveness of the pill. Feel free to take a pregnancy test around the time you expect to get your period, but i'm almost sure it'll be negative. (i'm on the pill and manage to convince myself almost every month that I might be pregnant!) since you've been on the pill for only a month, you might still be experiencing side effects from it... It also might just be happening for a number of reasons unrelated to pregnancy.

The syptoms you are experiencing might be your body's reaction to the birth control pills. Your body might be having a time adjusting to the estrogen levels in the pills. If you don't miss a period and the symptoms continue, talk to your doctor. She might have to adjust the dosage for you or offer you a different type of birth control.