ABNORMAL PERIOD AFTER STOP TAKING BIRTHCONTROL!! HELP`

I have been on birth control for a year, and I decided to skip a month last month. I got my period almost on time (4 days later then the regular time i usually got it in the previous months), and i decided to start taking my birth control again through the "day 1 method", which is u start taking your pill on the very 1st day of ur next period, opposed to every onth before i would do the "sunday after" method. Even before taking Birth Control i always had very light and short periods about 2-4 days. This period has been going on 8 days. It is very very heavy and it does not appear to be stopping. I am just curious if this is a sid effect from the month i skipped? or is perhaps it could possibly be a miscarriage? if anyone has any input it would be greatly appreciated