I'm not too sure about this, I was put on primulut to bring on a bleed. I think it is a high level progesterone pill. It effects the lining ..thickening it when you stop taking it causing a bleed to occur. I usually took it 5-7 days and then stopped and with a few days I would get AF. I always took mine in the schedule time, maybe the symtoms are related to the high levels of progesterone but then again!! Ahh I'm no help
Bec