IUD Mirena

Hello 🙂
So Today I got the IUD for the first time. I was nervous but I needed something where I didn't have to take everyday and I'm bad at that stuff and might forget 🙁 yeah yeah, so I had a panic attack in the process because I had no idea what was expected and I didn't know which one I want so I got the Mirena. Plus I'm breastfeeding so I can get it and still have milk. So I decided to look it up and saw side effects and lawsuits and how it can move and implant in your skin 😳😳 maybe I'm freaking myself out. But I was wondering if any one you had/have it and liked it or your experiences with it. What I'm  wondering is that it's just floating there if you are having sex doesn't it move so when he cums wouldn't that cum get threw because your butts in the air and it's moved or does it just sit in place and doesn't move at all? And after you get it out in can you have sex or do u have to wait ? Sorry I'm just trying to see if I made a good choice.