Not fair!

Yesterday I played once more in a match for the University chess team, this time the Second team instead of the Third one. Playing with black on Board 5, the game started as a sort of Grunfeld but quickly left theoretical grounds. In a confused position my opponent blundered and lost a knight, with the possibility of getting the exchange as compensation (so he would end with rook against bishop and knight, a fightable situation). He chose instead to keep the bishop, capture a pawn and try for an attack. This proved to be a mistake as I easily parried the attack and recovered quickly the pawn winning an extra one, at which point with a piece and a pawn down and no compensation he could have resigned straight away. He continued to play for several moves, though, until we reached the following position:

As you see the position holds no hope for White. I have just played 25... Ne4, with the threat of Nf2+ followed by Nd3+ winning the exchange. My opponent replied 26. Qc4, at which my eyes boggled: he is allowing me to make Philidor's mate! I had never before had an opportunity to do Philidor's mate, which is by far the most elegant of the common and recurring patterns of checkmate. After looking once and again at the position to be sure there was no snare in it, I proceeded: 26... Nf2+ 17. Kg1 Nh3+ .......

And my opponent resigned. What a frustration! Not fair.