White's plan at move 9 is wrong. He should instead play 9. Rb1 and follow up with b4-b5 to create weaknesses in your queenside pawn structure. Look up "Minority Attack" for a more in depth discussion of this plan.
White shouldn't willingly trade his kingside pieces. He left his king with no defenders. This makes black's job easy since in this pawn structure black will be naturally attacking on the kingside.
Finally white makes a tactical error at 22. Ne5 this simply loses a piece since after 22. ... Rxe5 the rook cannot be captured due to the forced mate that follows.
9. ... a6 seems unncessary at the time, you can probably move forward with a more active plan at that time.
17. ... Qa5 doesn't look right to me. It ignores the threat of 18. f3 forking the knight and bishop. Maybe you had a response to this, but you didn't annotate so who knows. Also, your queen is going to the wrong side of the board. White bails you out by taking the e4 knight and clearing the 5th rank allowing you to transfer your queen to the kingside easily. A prefer a plan of pushing the f-pawn to f4 to open central lines since your opponent is focused on the queenside.
I won this game against the highest rated player I have ever beaten, but I was wondering if there was any errors from either player etc...??? any comment would be very appreciated