Here is the game. I was bored of tactics trainer instead of live chess I go into computer chess, and I manage to blunder a piece in the opening against the french :(

From that point on I had to concentrate to save my honour :) And I managed to create a big attack. 

Note to self 

study openings opening openings! 

Since your opponent also blundered a piece earlier, it just came out even.  By move 15 you're only down a pawn, and Black is uncastled and undeveloped (except for his queen).  I would definitely take your position.

Btw 21 fe+ was faster (21... Kxe7 22 Qf7+ and mate next move).

true but after Bc5 I only noticed there was no way I would avoid Bxf+ and I think subcousciently I prefered to loose hte piece instead lol

Tactics tactics tactics its what I do :) at least I try don't really sure it works but I got more than 100 hours on tactcs trainer and rated 2300+ there

Btw 21 fe+ was faster (21... Kxe7 22 Qf7+ and mate next move).

that was what I played rigth? fxe QxN did I miss any mate?

No, you played 21 fg+.  21 fe+ was a mate in 3.

21. fxe7+ kxe7 22. Qf7+ Kxd6 23. Qc7# is what he meant..

BTW in your notes you said you thought he can't take the pawn.. maybe a 1600 just sees 6 pleis ahead? (that's too low but makes sense when you count the moves after cxd4 up to Qxd4)

if it is, then it's like computer evaluated that after 1.cxd4 cxd4 2. Nxd4 Nxd4 3. Qxd4 Bb5+ (it's 6plies already) and material is still even so it's safe to grab the pawn.. i've read somewhere that it's the horizon effect something..

because if the computer saw Bc5 in advance the knight can retreat safely right? and there's no real trouble after Bxf2+? or is there?

true missed the Qc7# thats why I suck :(