You might want to see about an MRI of foot and ankle too. Sounds a lot like how both my ankles react and I've quite a few torn and frayed ligaments in there. For the most part they've improved with a bunch of muscle relaxers and the gabapentin, but if I miss too many doses of the relaxatants they swell right back up again and are very painful to move or walk on for awhile, at least a few weeks. Fingers crossed that's not the problem, but there's too many muscles, tendons and ligaments in the feet and ankles to trust a dx to an X-Ray IMO. And they generally don't react well to long bouts of spasms.

Hope you feel better soon