Neuropathy / Foot pain ?

I am on T3 @ 45 mcg and have developed neuropathy, foot/leg muscle pain and plantar fasciitis

I experience most of the muscle pain when I get from from sitting or laying down for a few minutes and start walking.

Any clue as to what this is? I've stopped all other meds to try to isolate and see if this is related to l-thyronine (T3).

Literature says it thyrotoxicity can develop neuropathy, as well as hypothyroid conditions. my pain got worse as I increased upwards of 65 mcg and I reduced to 35-45 to see if it helped, and it did a little.

Is 65 mcg too high a dose?

Thanks