Can Taking Ortho Tricyclen Lo Result In Breakthrough Bleeding?

Hello,
I am currently 24 years old and have been on ortho tricyclen lo for 5 years now. In the past two months I have been having break through bleeding and I do not know why. Last month it was light for a about a week and a half ( then got my expected period which was not as heavy) and it happened again this month (heavier this time). I am due for my expected period next week and have been bleeding already for 7 days. In addition I have extremely sore breasts and I can't seem to fall asleep at night because of cramps and the soreness. This leaves me tired and groggy all day. Is there a reason why this is happening? Should I be concerned? Thank You, Kassy