Period starting before done birth control pills?

It depends on how long you have been on birth control. I have been on it since I was 13 and sometimes I still spot or have my period early. This is mainly normal and yes you should occasionally get cramps. Like I said, if you are just now starting the birth control you will get cramps and all that awesome "sarcastically" stuff.

If it continues and your still worried, talk to your obgyn or your health care provider. And they can take it from there :)

Edit: This will still happen, birth control doesn't make everything perfect. First I would try and go on a higher dosage, and if that still doesn't work, try a new brand.

It happens sometimes. The pills don't always make everything perfectly regular. But if the heavier period and cramping don't stop after a couple of months, I'd say yes, try another brand.

Yes, talk to your doctor.