Mirena question!

Ok so I got my first IUD on Oct 26 and I had a really long period (if it even was a period). It lasted almost 2 weeks. But my issue now is, my boyfriend can feel the strings and they're tight to where it hurts him. How long did it take for the strings to soften up and move behind your cervix? I've already been back to the doc to check on it and the Mirena is exactly where it's supposed to be. I couldn't feel them myself before I went it the doc but now I can totally feel them.