IUD bleeding

I've almost had my IUD ( hormonal ) for almost a year and have experienced very minimal light spotting for a day or 2 as my period for 6 months. Last Saturday I started a real period that lasted until Wednesday and returned today again full force (Friday). Has anyone experienced this? This is pretty heavy bleeding like leaking from a tampon, prior to getting my iud I never had any symptoms nor heavy bleeding and short periods.