Greetings
I have the same issues with my legs, the swelling, cramping and sensations as you have as well. I was diagnosed with autoimune Hashimoto thyroiditis after being Hypo for many years. I had the TSH, Free T3 and Free T4 plus Anti Thyroglobulin level and Anti Thyroid Peroixidase tests done - my T3 is low and hope to introduce Cytomel soon but since I now live in Asia am trying to get hold of Cytomel T3.
I also do Qigong and jumping exercises early in the morning that has helped to lesson the swelling as it is a way to activate the lymphatic system. I also drink 6 glasses of water per day - when I have more my legs swell and when I have less the same happens. I have cut out soya, peanuts, milk and dairy products, have organic black coffee as the latest research indicates that is contains a lof of benefits but have not more than 3 or 4 cups in the day - none after 5 in the afternoon. Also cut out all forms of wheat and corn, have Ezekiel bread and cook according to the ways used in Nourishing traditions - a cookbook from the USA. I soak nuts and dry them as per this book and eat for health and limit the use of supplements. As soon as I use Vitamin D tablets - I seem to develop a rash and my body itches - cut that out too and try to spend about 10 minutes in the sun each day when possible.
Hope this is of some help to you
Please post your latest labs with ranges provided.
Possible causes:
Hypothyroid can cause the burning sensation. Low free T3 levels.
Levothyroxine in too low a dose.
Alochol for some people, and its effects of dehydration (calves are the give away here).
In my case and others, T3 med helped some with the leg and feet burning problems.