What happened to me?

I was having sex with my SO and it’s the first time we’ve done it in a while since I got the IUD so I was scared it would hurt. During it soon before he finished I was crying I was in to much emotional pain. I didn’t tell him to stop because I knew he was close and he couldn’t see my face to tell that there was something wrong but I still feel horrible... I don’t know what’s happening to me