New IUD question...

So I just got my first IUD, I am 13 weeks postpartum. The first day I was feeling a little stabbing/pricking. Best way to describe it is when you cut a tag off a new shirt and miss the inside plastic piece and you feel it poking you. So question one, is that normal? I do feel better today.

Second question, my husband and I make love twice since I got it and each time he felt like he was being poked. He hurt and had to stop. Can the string hurt him? I thought guys couldn't feel it? I'm due to go in to have it checked in 6 weeks. Wondering if I need to go in sooner.