When Harry met Dean

Last night I played Harry Ratner in round 3 of the Derbyshire Individual tournament. We agreed a draw after my 38th move, plenty of pieces left but it looked very even and difficult to get an advantage. I'd appreciate any advice on what I could have done differently throughout the game.

I think in general I could have moved my queen about more to threaten his pieces and pawns. I think he had the advantage through most of the game with more active pieces, so I tried to keep the game tight and not leave anything unprotected. A few months ago I would have done something wreckless which allowed a tactic against me, but I think I'm learning to be more patient when under attack.

[Event "Derbyshire Individual 07/08"]
[Date "2008.01.08"]
[Round "3"]
[White "Dean Madden"]
[Black "Harry Ratner"]
[Result "1/2-1/2"]
[ECO "A05"]

1. e4 c5 2. Nf3 d6 3. g3 Nf6 4. d3 g6 5. Bg2 Bg7 6. O-O Nc6 7. Nbd2 Bd7 8. Nh4 Rc8 9. f4 b5 10. f5 Qb6 11. fxg6 hxg6 12. Ndf3 Bg4 13. h3 Bxf3 14. Nxf3 Nh5 15. Qe1 Ne5 16. g4 Nxf3+ 17. Rxf3 Nf6 18. Be3 Nd7 19. Rb1 Ne5 20. Rf2 Qc7 21. Bf4 e6 22. Bxe5 Bxe5 23. Rf3 c4 24. c3 cxd3 25. Rxd3 Rd8 26. Rbd1 Rd7 27. Kh1 Rh7 28. Rf3 Ke7 29. Bf1 a6 30. Rc1 Qb7 31. Qe2 Bg7 32. b3 Rc7 33. c4 Rc8 34. Qe1 bxc4 35. Bxc4 Rch8 36. Bf1 Rh4 37. Kg2 R8h7 38. Rd1 1/2-1/2

The final position is below:

Fritz threw up an interesting move I could have played in the last two moves: Qa5. This would have created below:

If he played Rc8, I could take the rook, he'd take back with the queen, then I could skewer king and rook with Qg5. If he plays Rxg4, I can fork queen and king with Rc7. Moving his queen first allows Rc7 followed by the other rook taking f7 and forcing a mate. Very interesting position and am not surprised I missed it.