Hey 1WelshGirl,

Sorry to hear of your terrible symptoms. Something you may not be aware of is Metatarsal Pads that fit over your toes and under your socks and cushion the balls of your feet.
I get temporary hyper-sensitivity of the balls of my feet (metatarsalgia) if I overdo planks and these pads for me allow me to walk and run without discomfort as and when. I appreciate your symptoms are in a different world, but Metatarsal Pads maybe worth trying. I paid £11.99 for 2 pairs from Amazon.

Pob gorau cariad,

Atty