Can your period be 5 days late with an IUD?

Sure! Since an IUD or a condom are a mechanical barrier that stops the sperm and egg from meeting they have no impact on the length of your cycle.

Answer

you should be sure you aren't having other pregnancy symptoms take a home test, if you were always regular you might be pregnant like me, i always had 26 day cycles and this month i was 5 days late and now I'm pregnant