Thanks for your reply taht will be useful for other users as well.
My case is abit diffrent than what you describe: I DID NOT publish the article as it was only partially translated.
But I think I understood my mistake:
After having closed my edit page by mistake, I reopened it and did not see anything appear from my work.
The more the popup window inviting me to start the translation appeared like if the topic was not saved.
I thought it was lost and did some edits on the empty page that were automatically saved overwriting my work that was still there but in the background.
Now when I reopen the page it still appears empty but I retrieve my work by clicking the link "All translations" and open the draft page.
It takes a while before the translated colum is populated, so you can believe again you lost your work and do wrong things again.
Just want to clarify to prevent other beginners to fall in the same trap.
By the way is this procedure explained somewhere?
Mean retrieving saved work BEFORE publishing for the very first time (draft).
Friendly from Belgium