tearing my hair out.

hey my SO and i are 4 months TTC i came off cerazette in june. 
my periods have been 29, 30, 28 calender days and this month 24 days but this months started off light brown then went pink. 
ive now been bleeding a week (usually only 4 days) really heavy and flooding i called the gp who said this can be normal to have a one off like that!
im still cramping after a week and im totally emptional! anyone else had the same? how long will this go on for? im at my wits end!