Welcome to online chess. Mouse slips happen. It's a part of the game.
To have to confirm every single move would be ridiculous, especially in blitz games.
Other chess servers have takeback request features. Of course, your opponent is never obligated to accept the request. Again, welcome to online chess.
Sometimes you just make mouse slips and lose and it's so unfair! It would be nice to include a take back option or a move confirmation option.
This is one of my good games that I lost because of a mouse slip, not a blunder!
http://www.chess.com/livechess/game?id=768910651