Can you find the swindle?

 This is from an OTB tournament game I played today.

My position was already utterly lost when I blundered and snatched a pawn Qxd6... he replied with Nf7 forking both my rooks and the Queen. Which leaves us with the puzzle postion.

I won from this ridiculously lost position. Now, to be fair, this is NOT a legit puzzle -- there is NO truly winning move here. An honest man could have resigned. But as I gazed at the board in despair, I saw glimmer of evil hope -- I saw a move -- "if he just takes material greedily and overconfidently without really looking at the need for defense, I've got a win!" My heart thudded in my mouth. The clock blinked.  I tried to look bored and hopeless and I made my dirty filthy move. He fell for it! He blundered -- gobbling material and losing the game, instantly!

Can you find my swindle?

Haha, I bet he was mad! Nice one!

Your opponent shouldn't have grabbe the material that quickly. The fork was still in tact and could've taken whenever.

Didn't spend more than about 30 seconds looking, but totally didn't spot it :).

lol, great move

Tactics is the most important element in the middle game -----TARRASCH

Tactics is attack. Tactics is the use of smashing moves. Tactis, then,  is the imposition of your will on your enemy.

Your opponent failed to recognize  the threat, your move Queen to b5, a move which threatens something, either winning a piece, gaining ground, or forging ahead in development.  But your's was a special kind of threat aimed directly at the King and is called the "mating attack". Good counter-move.

Is this position really lost for Black?

If White doesnt take the rook, instead move the queen to avoid the fork Black can still play Nc4 with the same plan. 

Black's position is pretty horrible. After Qb4 White answers a3 and will soon go up the exchange and two pawns. I'd play on looking for a miracle/mistake, but Black's dead have no illusions. 

Correction: Its not Queen to b5, itsQb4

 Sorry, typo error