I have an endometriotic cyst in left ovary. Was prescribed dinogest 2mg. I take it from day 2 of periods for 20 days and stop according doctor's advice. I usually get my periods within 5 to 6 days after stopping the medicine. Periods was normal no pain but after finishing 3 cycles periods have been delayed. Last month my period lasted 1 day and this month i haven't got it yet after 7 days. Is this normal? Should i start another pack if my periods doesn't come at all?