Wow, your description of what I have felt at times hits the nail. I could be sitting and watching TV and I just do not feel like I am breathing right, or my heart is not beating right. I feel I have to concentrate on my breathing sometime to make sure I am ok. I have never suffered from anxiety altough I did have what I call nervous breakdowns on a former birth control-the pill with very low hormones-that I why I got the Mirena. I haven't felt it in a little while. It just comes and goes for no reason. I too, have many of the other symptons and have finally decided to get this thing taken out.