Lost the game in last moment

I was having upper hand during most of the game. Lost it in the final moment.

1. e4 c6 2. d4 d5 3. e5 Bf5 4. Bd3 Bxd3 5. Qxd3 e6 6. Nf3 c5 7. c3 Nc6 8. O-O Rc8 9. Nbd2 c4 10. Qe2 b5 11. a3 a5 12. Rd1 Rb8 13. b3 b4 14. bxc4 b3 15. Rb1 a4 16. cxd5 Qxd5 17. Qa6 Na5 18. Bb2 Ne7 19. Qe2 Nc8 20. Nh4 Nb6 21. Ndf3 Nbc4 22. Bc1 Nxa3 23. Ra1 N5c4 24. Bxa3 Nxa3 25. Qb2 Qb5 26. Rxa3 Bxa3 27. Qxa3 h6 28. Nd2 Rb6 29. Ne4 Kd7 30. Nc5+ Kc7 31. Nxa4 Ra8 32. Qe7+ Kb8 33. Nxb6 Qxb6 34. Qf8+ Kc7 35. Qxf7+ Kc6 36. Qxe6+ Kb5 37. Qxb3+ Kc6 38. Qe6+ Kc7 39. Qf7+ Kc6 40. Qe6+ Kc7 41. Qf7+ Kc6 42. Qf3+ Kb5 43. Rb1+ Kc4 44. Rxb6 Ra1+ {White resigns} 0-1