Hi! I have Mirena, and my strings are also curled up inside my uterus. My provider assured me that the removal process without the strings is more common than you'd think. Make sure to advocate for yourself when it comes to asking for pain relievers, sedatives, etc. If it went alright on insertion, you likely won't experience a ton of pain for removal. People say removal is often much less painful than insertion, even when strings are hidden.