I'd say I cramped off and on for a week or so. They were mild cramps, not as bad as menstrual cramps, but my menstrual cramps pre-Mirena were really, really bad. I also got mine inserted 4 years after my last birth - I'd imagine a post-partum cervix/uterus is more easily irritated than your average. The spotting, btw, lasted for a really, really long time for me. At least a month in the "light period" stage, and then gradually less and less over time. Sometimes I'd get spotting several days in a row, then none for a week, then a heavier day, etc. It wasn't really predictable at all. I've had mine for about a year and a half now - I can't remember when the spotting stopped, but I'm generally on a regular cycle now (though it's short - maybe 21-24 days). I used to only get periods 3 or 4 times a year, and they were killers where I was curled up in a fetal position and couldn't leave the house for fear of bleeding though everything - so frequent, but very light and painless, periods were a good trade off for me. I seem to be a rarity among people I know though - most bleed less frequently than before, or on the same cycle as pre-Mirena, but pretty much only spotting for a few days rather than a true period. Then there are the lucky ones who have cycles that completely stop.