I agree with some sort of nerve compression. It may not even be in your arm, but in your back or shoulder. Nerves are tricky that way. Try some mild stretching of your back and shoulder and then some ice. If it hurts, stop. If it feels better, your on to someting.
Also look at the possibility that you may have more than one issue.
Stay away from cats, they could reactivate the condition. 
We’re putting requests for medical advice, anecdotes, and commentary in IMHO these days, so I’ll move this thither.
twickster, MPSIMS moderator
nvm
I love that **prr **posts an update saying “Here’s what it was, if anybody was wondering,” and it’s at that point that people just read the OP, skipping right past his follow-up. On a one-page thread with only two dozen posts.
Stay classy, everybody.