Trinessa Lo

I've been on various types of birth control in the past, but I recently experienced something new. I was on the Mirena for 4years, then had it removed and switched to the pill (Trinessa Lo). I just started my third pack. On the second pack, I started my period a week early (the duration was the same- about 4-5 days), and when I asked my doctor about it she said to just continue tracking and to possibly take a pregnancy test (it was negative). My question is if anyone else has had this happen before? If so, would you restart your next pack on the day your period started or no?