I lead church services. prepare sermons mostly on our home computer.

My wife wanted to use it, so I saved some 'dot points' onto a memory stick and transferred to my laptop, which runs Win 10.

For some reason I did not transfer from the memory stick to the "C" drive of the laptop, and started expanding my dot points.

Had two pages done, when - instead of them, which had not been saved, I had the last twelve words that I had typed, at the top of Page 1!  Nothing else.

My question.!

Which key, or combination of two keys, did I hit to wipe my work beyond recall?

[I understand that because I was not on 'C' drive, the Word 2016 doc did not auto save, and I was nowhere near the delete key.]