Knight Sac Pretty cool

Your board says White won. The game resulted in a win for Black. The Knight sack did nothing. I am sorry to say I am confused. Were you playing as Black or White? 

I was playing black. The knight sac did a lot. For instance if white would have taken the bishop it was forced mate in 6. Not sure why it says white won? Losing the knight was fine as the threat of mate in 1 allowed the recapture of the bishop and blacks bishop pair keep white from mounting any counter attack. Take a deeper look.

I see it. Good job.

Taking the pawn was a mistake. Perhaps Bb5+ would have served better, or just instead move the OTHER knight,

8 c4 would have also been better.

Because it strikes the center and in addition gains counterplay, though it may seem redundant to 8... d4 or 8... dxc4, those are both bad alternatives.

After 8... dxc4?!, white just simply plays Bxc6+, black loses his pround center.

After 8... d4?, white plays Qc3 with a lot of counterplay.

Another thing? when you did the Ng3+ thingy why not Kxh2? It's not like the Q's in danger from a discovered...

Also the move is not nf5. I was planning nf1 double check

Very nf1 check...very special and I had it all calculated too. The game went differently as shown above. But that would have been sweet to play nf1