Progesterone?

Sharee • Loving life with my sweet rainbow baby! 💗Amelia Nicole💗
I had my first IUI on Sunday the 11th at 36 hours past trigger. My doctor started me on the progesterone suppositories the next day. I had some cramping on Monday/Tuesday near my right ovary because that's where 2 of my 3 mature follicles were but after that just some twinges every now and then. 
But this afternoon I suddenly got period like cramps and they haven't stopped yet! I seriously feel like I'm starting my period but I still have over a week for that!! 
Has the progesterone ever done this to anyone?