it moved???

So I've had my IUD for about a year now and it's been wonderful. But a couple weeks ago I had rougher sex than usual and now whenever I check to see if it's still in place, the strings a lot longer and I can move it around more! I don't know if I should pull it out or move it or if this means I'm pregnant or something... I didn't experience any pain so I don't know if it's torn out and just floating in there or not... please help :(