I don't know what that dx means, but if resting for a short bit helps and you can get back up - I'd suggest seeing a podetirist and finding out if you have Morton's Neuroma or something similar.
I'm a big believer in orthodics (they pretty much saved my life so to speak) I grew up w/RA and the compensating I subconsciously did really messed my feet up. Now I have psoriatic arthritis in my feet and pretty much can't live w/o my inserts.
Good luck.
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