Was it a miscarriage?

I started taking the pill last month for the first time. Then this month something a little strange happened. 3 days after my period was supposed to start I began to get real bad cramps, worse than I have ever got before. The next morning I began to bleed so I figured the bad cramps was because of the birth control. Then later that day when I went to the bathroom a big clot fell, and that has never happened before. It was big enough to make a splash. After that the bad cramps went away. The period lasted a little longer than normally. I was wondering if this was a miscarriage or if it was the Birch control. Thank you to anybody that helps me.