I guess in our line of work it's easy to step on something accidentally and it hurts at the time but forgotton about. Because the feet don't get a good blood supply and you are walking on them a lot it can take months to get better.
I used to love the Bruffies when I had no choice but to 'push through the pain' LOL but now I'm soft I used RICE and my new favourite drug Diclofenac.
Re numbness could be a trapped nerve or even a knotted muscle in the forearm, even back or shoulder.
Get down the Docs you're mad if you don't get it diagnosed.
And, do people swap right left handed wanding now and then?