resetting I would only like to use a last resort... Afraid to loose my music collection.
Isn't there a button somewhere (that I may have hit inadvertently)?
There isn't a button that could have cused this. Although, when you reinstall the application, you won't lose any music except for local tracks you and offline music, which can all be resynced. All music that you have added to your Spotify collection is stored on Spotify's servers, so you won't have to re-add everything.
Like @Jordi said, I recommend you try a clean reinstall.
If that doesn't work, let us know!