The position is extremely difficult to hold onto, your queen and white squared bishop are eyeing down an eventual checkmate.
You have a passed pawn, after playing e7, check, black losses a rook and that forces on move 22 black to play Qe7 to stop your pawn advancing, as a result your knight to h6, is checkmate.
So you did have an immediate win :)
I had a good attack but I did not see an immediate win for myself.Why did my opponent resigned here?