My period lasts 2 days max. i'm taking puregon then have iui. would taking progesterone after iui help especially because of my short period?

No: Progesterone may prolong the time until you get your period but not the duration and heaviness of your flow. The duration and heaviness is associated with many factors including the amount of estrogen your ovaries produced, the thickness of your endometrial lining, the rate of decline of Progesterone from your system and many other factors.