I had it for just over a year, and had it removed 5 weeks ago. Same awful side effects (anxiety, depression, acne, libido loss, constant tired, breast pain, back pain, cramping, bleeding, night sweats, severely dry skin... the list is endless). I feel terrific now - not tired, no pain, I can sleep again, and I have already easily lost most of the weight which I could not shift with hard work while I had the mirena.
I think honestly we are part of a Conspiracy
as none of these side effects are mentioned anywhere and doctors keep saying "oh you are the first to have a problem".. I myself was told by my doctor that it was all in my head, I wanted to get rid of this thing 3 weeks after it was inserted and I was getting serious anxiety attacks, something which I had never felt before in my life.
I was dumbstruck enough about it to do significant searching around the european forums and there are an immense amount of complaints and negative reviews. Whilst the amount of hormones released is "low", the device messes with you more than others. I read a study that was conducted by a clinic in Austria where they believe what is actually triggered in the body is an "early menopause" due the way the menstrual cycle is suppressed. Hence so many of the side effects that are associated with serious hormonal fluctuations during menopause.
I have a copper IUD again now, have heavy periods but at least I have energy and feel better. You can't win 'em all... but to say that it was all in my head would mean I was insane and crazy.
I have nothing good to say about mirena and would recommend women to stay away from it. I cannot express how awful I felt over the last 15 months, and how badly my hormones and body felt messed with. Who knows what kind of lawsuits will be around in a few years time over this thing..