Hi
When charging your Apple Watch, be sure to follow Apple's safety and handling instructions (see the links below) and also note that it is normal for your watch, power adapter and charging cable to become warm (but not hot) when connected to power.
Battery life varies depending on use and other factors. Examples are detailed here:
http://www.apple.com/watch/battery.html
Apple's tips for maximising battery life on Apple Watch are detailed here:
http://www.apple.com/batteries/maximizing-performance/#watchtips
If your Apple Watch is experiencing significantly shorter battery life than Apple's examples suggest that you should expect, then the following steps may help, having previously resolved battery life issues for some users:
If you have not yet done so, update your iPhone and Apple Watch to the latest software, starting with your iPhone (be sure to make a backup first):
Restart both your iPhone and your Apple Watch, turning both off together and then restarting your iPhone first:
Unpair and re-pair your watch:
Some users have previously experienced battery life issues in connection with using corporate profiles and/or Exchange Calendars. If you are using an Exchange Calendar, one or more of these steps may help:
- Archive your Exchange Calendar for all items before today.
- Remove / delete all old inbox messages relating to calendar invites (accept and decline notifications).
- Create a rule in your Outlook Mail account that moves all future accept and decline replies, immediately upon receipt, into a separate mail folder that does not sync with your iPhone and Apple Watch.
- Check your Exchange Calendar for errors.
Finally, it may help to:
- Remove third-party apps from the Dock and/or from your watch and then monitor battery performance after adding them back, one at a time.
- Remove watch face complications and monitor battery performance as you add them back:
Having tried the previous steps, if either issue persists, I suggest contacting Apple Support (remote diagnostics and/or mail-in service may be available, if required), making a Genius Bar reservation or visiting an Apple Authorised Service Provider for assistance, including - if recommended - to have your watch inspected and serviced:
Apple Watch Service Answer Center - Apple Support