Great recovery from what looked to be a very rough spot. I wonder if your opponent suggested anyone else resign early after this defeat.
Volatile game with sacrifices by both sides
I think you were fine after 18 Qh7+ Kf8 19 g6 ( 19 Gh8+ Kf7 and I don't see White doing any real damage. Sac the rook back on g5 and hold a material advantage.) Qf6 (you should avoid 20 Qh8+ Ke7 21 Qh4+ Kd6 22 Bf4+ Rf4 23 Qf4+ Ke7 24 Qf7+ Kd6 25 Qg7 threatening to do more damage with the pawn in there. ).
19 ...
Some thoughts on your game with some variations.
I did the evaluation myself without the aide of a computer, so I apologize for any glaring errors in my lines.
Extensive move list.
Arguably the best defense for Black, Ng8 is the main difference form the above variation rather than the King walk, but still an advantage for White.
This game involves a sacrifice by White (my opponent), with the favour returned soon after in order to counter White's mating threats. It's over in 22 moves (I had mate in two), but I think White could have at least got a drawing position, possibly better.
Anyway, any thoughts on whether I should have allowed the sacrifice in the first place (although I didn't actually consider it before it happened), and whether my defence/counter-attack was sound, would be helpful.