nraas

What does it mean ?

And question:
In-game there is the option "Tag information", in it the option
"Lifetime Happiness" with the word spendable in the Tag shown then, but this is not listed in the localization of Tagger.
Where is it then?

"Uh oh" is an expression of dismay or dread. In the context you are seeing it though, an equivalent expression would be "Oops."