congratulations on the win....

However, that was a game against a much lower rated player which continually made weakening moves to his position and finished it off with a gross tactical oversight.  After k-b2 you do definitely have a HUGE positional advantage.  But, that should be expected. 

Your n-h4 looks suspicious to me.  After b-e3 you have to play b-f5(otherwise h3 and g4 fork the knight and bishop) and white plays h3 and g4 anyways and your king looks suspicious on the kingside(white can castle queenside and has his attack started already) so you probably castle queenside.   In that case white can actually castle on either side and has the nice e4 break.

After saying all that I realized you lose a piece by force after 1. b-e3,  B-f5 2.  h3, now you have to either play g6 to open up a spot for the knight(but then that loses the bishop) or you lose the knight. 

Now if you play d5 in response to b-e3 then simply bxd5 and you are in the same predicament(if O-O-0 then white responds with the same).

Again congrats on the win.  My intention isn't to destroy your spirit.  I simply thought it was a pretty instructive mistake which you could learn from. 

And again you did take advantage of whites mistakes very well:D

14. f3 was awesomely bad.