After I castled I was tempted to sac my knight in the center, hoping to prevent Black to castle and open the e file on his King.
http://en.lichess.org/Cg3bN6t1It worked out well.
This is a standard motif in a lot of openings, but you spoiled it by playing a3. You only won because the opponent missed the chance to disallow d6 by playing Bd6 himself. Sorry, not so great game.
Indeed I spoiled it a bit with a3, but still I'm glad I had the good intuition of 8. Nd5.
I think that sac was too early, with 10..Bd6 Black is ok.