Mirena and hormones

My doctor pushed the IUD through my uterus upon insertion. I didn't know until about three weeks later when the pain wouldn't go away. They found the IUD on the outside of my uterus. Now I am four days late for my period this month. ( I had the mirena before and it stopped my period completely) Im wondering if the Mirena is still giving off hormones that are stopping my period even though its not in the right place or if I should be worried about pregnancy.