Hi, I Have Been Having Irregular Periods Recently. Almost Once

Hi, I have been having irregular periods recently. Almost once every 2 weeks and the interval ones are of minimal bleeding, for a few days. My doctor prescribed me with Duphaston 10mg for 10 days (2 pills a day), starting from day 5 after the interval bleeding ends. It is now day 6 of my medication, 2 weeks after the last interval bleeding and I am getting my menses again. Is it normal for me to get my menses during my Duphaston medication? Can I still continue taking the medication during my menstrual period? Thanks!