I know with mast cell the worse you get the more symptoms you can have in other words if you're not eating the proper diet and you're stressing too much Etc other things can affect it such as chemicals. I also deal with a lot of heart tachycardia and palpitations at first I thought it was the pots but I'm now realizing it's the mast cell. Once I started eating the Mast Cell diet I have improved somewhat. But I also do many other things strengthen my immune system and lower what I'm exposed to like chemicals Wi-Fi electromagnetic frequency and processed food. Hope this helps.

My feet do that. The muscles/tendons start to curl up tight. I started taking ReMag, a magnesium supplement. It really helps sooth nerve, joint pain for me. I'm also hypothyroid which can have low magnesium. My bloodwork never showed clinical low but my low is different than the average low.