I figured that I would benefit more from d2-d4 rather than d3-d4, since the e5 pawn makes it difficult for black to defend his ill-advanced knight.
3... e6 4. Ng1f3 g5
? Premature attack. Must develop first! Tactically it also seems to lose the g4 pawn (as in the game continuation.)
5. Bf1d3 f5
? Blind aggression. Still has only developed one piece. Opens the Black king up to attack.
6. exf6 d5
Like a bull in a chinashop! Why not recapture via Nxf6? repositioning the knight, you lose a pawn and the knight is pinned, but the alternative seems worse.
7. Bd3xe4 dxe4 8. Nf3xg5 e5
?! Still not developing anything and allows Qh4+.
9. Qd1h5 Ke8d7 10. Qh5f7 Kd7c6 11. dxe5 Bc8g4
Good placing for the Bishop, but possibly allows tactics since it is undefended.
12. O-O Bf8b4
Another good posting, but again it is undefended.
13. Ng5xe4
?! Sure I win the pawn, but better was Be3 followed by Nc3 and then a real attack can begin.