Get your vitamin d levels tested, optimal levels are between 70-90ng/ml. Folks who have MS and have had their vitamin d levels tested have consistently been found to be deficient. When they get their levels up, their symptoms disappear.
I'm not saying that you've got MS, but low vitamin D levels contribute to many, many health issues. Also, if you're not supplementing with a really good multi-mineral AND a separate B-complex (minimum 50mg - 100mg ideal) you should be. Synthetic hormones like Mirena deplete these vitamins from your body which cause different set of symptoms similar to MS. Get your vitamin B12 levels tested too. Optimal ranges are in the upper 800's.
Taking milk thistle or N-acetyl-cysteine will help the liver detox the synthetic hormones out better.
Evening primrose oil and vitex can help balance your hormones.
You also might want to consider getting a 24hr cortisol saliva test done, The IUD most probably has stressed your adrenals. canaryclub.org has adrenal test kits if your doctor can't order one for you. Stressed adrenals can cause, fatigue, anxiety, weakness to the point of tremors.