Where I'd go wrong?

I just resigned the following game after having a winning opening and middlegame position (at least in my opinion). Would anyone care to review this game and let me know where I went wrong. I know some of my moves were questionable but could I have drawn here?

1. e2-e4 e7-e5 2. f2-f4 f7-f6 3. f4xe5 Qd8-e7 4. d2-d4 f6xe5 5. Qd1-h5+ g7-g6 6. Qh5xe5 Qe7xe5 7. d4xe5 Bf8-g7 8. Ng1-f3 Nb8-c6 9. Bc1-f4 Ng8-h6 10. Nb1-c3 Nh6-f7 11. Nc3-d5 Ke8-d8 12. e5-e6 d7xe6 13. Nd5xc7 e6-e5 14. Nc7xa8 e5xf4 15. O-O-O Bc8-d7 16. Bf1-b5 Nf7-e5 17. Rd1-d5 Kd8-e7 18. Nf3xe5 Bg7xe5 19. Bb5xc6 Bd7xc6 20. Rd5xe5+ Ke7-f6 21. Re5-c5 Rh8xa8 22. Rh1-e1 Ra8-e8 23. e4-e5+ Kf6-e6 24. g2-g3 f4-f3 25. Rc5-c3 f3-f2 26. Rc3xc6+ b7xc6 27. Re1-f1 Re8-f8 28. Kc1-d2 Ke6xe5 29. Kd2-e3 g6-g5 30. c2-c4 g5-g4 31. b2-b4 Rf8-f3+ 32. Ke3-e2 Ke5-d4 33. c4-c5 a7-a6 34. Rf1xf2 Rf3xf2+ 35. Ke2xf2 Kd4-c4 36. Kf2-e3 *

I agree that you have a better opening then your opponent. Untill move 21 your still in a winning position.
Then Re1 is not the best solution. I would prefer Rf1 here and then go with the King to the center and support the pawn on the e-file.
On move 24 g3 gives your opponent a passed pawn for free, Re2 would be much stronger.
Then 25. Rc3 f2 makes the game equal again. You still had the chance to stop the passed pawn if you had played 25 Kd2.
Until move 29 you go oke, but on move 30 you have to play Rxf2.
Or if you did not want to at that moment stop de g pawn by playing 30 g4 preventing that his Rook come to f3.

Thank you for the analysis. I missed the move Rf3 and once he played that I realized that my position was too cramped. Also, the moves c4 and b4 were completely unnecessary and made in haste so I deserved to lose after that point.