I developed every symptom you listed, except for sensitivity to heat. I had sensitivity to cold.
I've been trying to detox the copper from the IUD with a various assortment of supplements but I've realized that the protocol that I am using to detox the copper is very similar to the protocol they recommend to unblock the Methylation cycle. The methylation cycle is important for detoxification (so obviously, if its blocked... thats a problem).
I don't know if it would work for Mirena users but it basically involves taking a few supplements similar to the ones you are already taking. Taking a multi-vitamin, fatty acids, and most importantly the B vitamins should be in their active form.
Like I said - I don't know if it would work for you but I don't see any harm in just changing some things around with your supplement protocol so that you were getting more of what is recommended for a blocked methylation cycle?