I watch causing Wrist and arm numbing and pain?

The encouragement to see a doctor isn't a bad one, and you always want to get at least a couple opinions before trying to zero in on what's causing the issue.

First off, try going a couple of days without wearing the Watch, and see if the problem persists. If it does, then it isn't the Watch, and is worth seeing a doctor about, likely one with a lot of knowledge about circulation or muscle pain.

If It doesn't persist when you aren't wearing the Watch, consider seeing a dermatologist to find out if you're having an allergic reaction: it could be to the ceramic back, as most people don't have reactions to stainless steel.

Double check to make sure you don't have the band too tight; if you normally wear watches, you probably have a good idea for what this feels like. The sensors on the Watch need some "pressure" on your wrist, but not a lot.

The pain factor makes me think you're likely having an allergic reaction, or it might be initial onset of carpal tunnel syndrome, but keep in mind I'm not a doctor, merely a layman who's done research into the carpal tunnel issue since I work in front of a computer all day and type really fast, so those are concerns of mine as well. 🙂

I hope the issue resolves for you; I'd hate to think someone couldn't enjoy the Watch because of medical concerns. 😟