Mirena bc&nightmares

Alright ladies, my youngest is 7.5 months old. I’ve had the non hormonal mirena iud for 6 months. I’ve hardly had any issues with it until the last few weeks. I have had some of the most god awful heart wrenching dreams, and they’re only about my oldest getting hurt/dying. Is this apart of the birth control? Or do I really just fear her dying that much, that I’m having nightmares from it? Idk. I feel like I’m going crazy because I’m hardly getting a good nights sleep. Has this happened to anyone? If so, what do I do to stop them?