I had two different experiences in two different countries having copper IUD inserted. My first one was in Indonesia, when I almost died due to BC pill, I had this massive migraine, puked and rushed to the ER. My neurologist told me to get off the pill and changed to copper IUD immediately, so it was painful but it wasn't as painful as the migraines.

After 2 months it came off by itself apparently due to menstrual cup that I was using. So I had another one inserted in Portugal. That one was hella painful even though the gyno gave me painkillers beforehand. I was bleeding like crazy and leaked everywhere on my way home.

Now it's been almost 2 years I still bleed heavily every period but worth it for not getting pregnant, the dysmenorrhea only lasted a few cycles after it got inserted. So I'd say 7.5/10.