3 week early period?

Ch
So I got on a different pill about a month ago. The side effects have been horrible. One week after my last period ended, I started again. At first I thought I was spotting, but there's been a lot of blood so I'm pretty sure it's my period. This bleeding has been going on for 8 consecutive days and counting. Is this a normal side effect of taking a new pill, or should I be concerned? My period has never been 3 weeks early before, and it's never been longer than 6 days...