Have I lost all my data?

I installed the wordpress spreadsheet plugin yesterday and spent several hours developing something that seemed to fit my purpose. Later I was having difficulty with another part of my website and to diagnose the problem I had to deactivate spreadsheet. Then when I reactivated spreadsheet, my post with the spreadsheet comes up with only the word [[spreadsheet]]

  1. Have I lost everything? If so, I am terribly disappointed, and I wish I had been forewarned.

  2. If I ever get the plugin to work again and reconstruct my data, how can I save the effort in some form of backup?

  3. How do I get the plugin to work again?

My broken wordpress website where the spreadsheet used to appear is wrbcsailaway.org

The spreadsheet data has now reappeared on my website, so I would like to remove this post, but I do not know how to do so.