Is there no way to undo changes?

I've just purchased and been learning your software and after spending nearly 2 hours creating my first blog post, saving multiple drafts along the way, I accidentally added a module block to the bottom of the article.

I clicked on the x to delete this module block, but somehow the x deleted the text block instead and so I lost 2 hours of work and there seems to be no way to recover it. It must have autosaved and over-ridden all of my work.

Is this correct, have I just deleted and lost all of that work?

It seems a fairly fundamental flaw in the software for this to happen.