I had mirena (levonorgestrel) iud inserted on friday. i've been having intense five out of ten cramping since. how long should this last? it was a difficult insertion.

Not much longer: The initial pain you're having is likely your uterus cramping around your iud and the iud getting situated in the uterus. They're getting to know each other and give them some time. If still painful next week, see your doctor to confirm good placement. In the meantime use heat packs, tylenol, (acetaminophen) and Ibuprofen 600mg every 6 hours to help with cramping. See a doctor for any foul odors/discharge.