What Causes Burning Sensation In The Feet While Having Grave S Disease?

Hi there! Just recently I started noticing sudden bursts of a warm feeling in my feet. It might just be in my big toe, only last maybe 2 seconds, and then go away. Then maybe again 1/2 hour later but in a different part of my foot. When walking up the stairs there it is again. Then I won t notice it again for a while. I do have some issues with instability in my lower back that we are working on and trying to strengthen that area and I m wondering if the foot issue is related or something different. I have Graves disease and have had many different issues while dealing with that, but have never had this issue before.