period again

Yudalis
so... I got my period on the 10th of this month, and started on birth control on the 15th. this is my first time on birth control and I know there are a lot of side effects the first few months. but I got my period again? I thought I was just spotting but no... it's a lot. is it normal?? I'm also having A LOT of cramps, which I usually don't have on my period. is that normal? please reply. thanks