I am on the progesterone only pill called cerelle and it is causing me constant periods, if i stop taking it will my period stop and how soon?

7-10 days: Progesterone only pills such as Cerelle are notorious for causing irregular, unpredictable bleeding. if you stop taking it, you will probably have an episode of heavy bleeding within about a week. After that, the bleeding should stop and you should resume normal cycles. If you still need contraception, it might be a good idea to get started on a combined estrogen/progesterone pill.