I have been taking Norethisterone to delay my period which didn t actually work as my period started five days early and I had only been taking the tablets for one day. I took them for a few days hoping that the bleeding would stop but it didn t so I eventually stopped taking them. I have been bleeding heavily now for four days and the blood is very very red. How long will this last? It has been quite painful too and I do not usally suffer with painful periods.