At move 8 what would you have done if Nxd4? He had three attackers on your two defenders. Also, 11... Bxd4 would have equalized at least for him, in fact, the knight was hanging for 2 turns before it finally fell. Moves 15-19 were a dropfest on his part. At move 20, I'm sorry to break it to you, you'd won, it was a fine time for him to resign. :P That was a reasonably well played game though, probably higher then your rating level.
P.S. I like the AOK jokes.
Let me know what you think of it.