11. Bf4?: I think h3 would be more effective, as it blocks the checkmate and kicks the knight out immediately. Also, now black can play 11... Nd3! attacking two pawns and your bishop. Lucky your opponent didn't.
14. Nf5?!: Trading a knight that was in the center for an undeveloped bishop is not a good thing to do in most cases. Also, at the end of the exchange, you have no center pawns.
A couple moves after that, almost all the moves were blunders :P
My first victoy with the Scotch game. I gave the Ruy Lopez a try, but it did not work for me. It seems like you have to know a whole lot of theory and there are too many variations that kept tripping me up. For a while I tried the Guico Piano or the four knits, but it seemed a bit dawish. So I decided to give the Scotch a try and I'm really liking it thus far. It seems to suite my style of play.
I was in time trouble and so was my opponent. I think I missed several wins, but in the end he played a few crap moves to give me decisive material advantage.