Missing strings?! (mirena)

So I have had my IUD for 5 years (this August will mark the literal 5). I had no issues until a year ago my OB couldn’t find the strings. I ended up getting a vaginal ultra sound, and they said they were find. I could usually feel the strings.

I went back yesterday for my yearly and she couldn’t find them again. She said she’s going to have to “explore” and is putting me on serious meds beforehand. I’m also tilted and have chronic pelvic pain. So it’s going to suck.

I tried to find them today and couldn’t. I’m scared. Thoughts?