What Causes Absence Of Periods With Pains And Cramps?

Hi, I have taken a naristerate injection which I only used once as it distracted my periods, the first month i had y periods but they were kind of weird course they dragged a bit. I skipped my periods for November but had horrible period pains and at the clinic they gave me trigestrel pills. I have taken the first 7 red ones now on the white row but still no periods,period pains are still there though. Kindly advise