I am a 67 year old woman. I was diagnosed with Hashimotos disease 30 years ago and have been on correct doses of medication since. (Blood test every 6 months). I also have cerebellar atrophy affecting my balance. (I can still walk on level ground without walking aids) I am still full in full time employment but have no anxiety or stress. For the last week I have been unnaturally tired. Why does my body feel so heavy?