My period is 8 days late but i have iud (mirena) is this is normal i have the iud for 2yrs now ?

Can be: A common side effect of the Mirena (levonorgestrel) iud is a change in the menstrual cycle. Half of women stop menstruating altogether once they have had the Mirena (levonorgestrel) for a year. Since it is an extremely effective form of birth control, it is unlikely you are pregnant. If you want to be certain, you might consider taking a home pregnancy test.