Emergency IUD...

I had sex on the day of my predicted ovulation date. After 86 hours and tried to get it the morning after pill. Was told I was 1 to 3 chance likely to get pregnant. Even with the pill. Was offered the emergency IUD option and was told it was much more effective plus reduced my chances. So I got it. Did I make a bad discussion? Let me know your experiences with the emergency Copper IUD? Thank you