Glad to help, a very helpful soul here gave me pretty much the same assistance when I started with hass in Nov.
Now I’ve dashboards, and automations all over 
The temp should update on its own every 2 minutes or so, iirc.
I really recommend breaking out your configuration.yaml file into smaller files.
It makes it easier to check for bugs, better readability, and you just experienced the ‘duplicate key error’ etc.
If you’re just starting, you’ll be amazed at the things you’ll have done very quickly - and that also means longer config files.
Lots of examples here that I used to get it done:
The formatting within the separate files is slightly different, so keep that in mind.
Enjoy, Hass is really an extraordinary thing!
I knew not a single bit of yaml or python 2 months ago. Now I can write APIs, didn’t think I had a bit of that in me!