How long will my period stop after taking new package of active birth control pills?

My doctor switched my birth control to a new one and this is my first period from the inactive pills. I took my new pack yesterday afternoon and my period basically stopped last night. Well, here it is 10:45 in the morning the next day and my period is back full force with extremely heavy bleeding and cramps. I used to bleed like this before ever taking birth control, so it s nothing new, but I was wondering when the bleeding should stop? Today will be my second day of active pills. Should I wait until tomorrow to call if it doesn t stop?