Know All (Vocabulary) button

So, I did a stupid thing. I am new to the site and I thought the “know all” button was for the words in your list and so I clicked it. When I did a box came up and said I had learned 196 new words. Is there any way to “undo” that? I love the site, but I’m still not quite sure how it all works…

You cannot undo it, but just go back and highlight the words that you do not know and save them. This will adjust the accounting.

Okay, thanks!