Annotated chess game

Why?

3...Nf6 Don't use 3 moves to move 2 pawns.

I don't know - I kinda like this move. True black doesnt really develop but white is not more developed than black so why worry? This ensures a long term space advantage - always nice especially as black!

Yes it was.

exd is clearly better with c5 to follow. or even Bc5 when the position is better for black, counter play on the queenside is nullified with Nc6 and a5 when black has better space on the kingside and will play there.

The best players, never look for a cheap early mate. They complete development 1st & then attack

5...Bc4 threatens mate in 1.

7...Bc5 is better.

...and not so easy to counter. E.g. 7...Bc5 8.Nd1 Ne4 9.Qxa8?? Qxf2ch 10.Nxf2 Bxf2# or 8.f3 Qf2ch 9.Kd1 Qxf1ch 10.Kc2 Bf5ch 11.Ne4 Nxe4 12.fxe4 Qxg2 etc. But it seems 8.Nge2 contains White's attack after 8...Qxf2ch 9.Kd1

8...Bc5+ gains a tempo.

Not a sac. Its a loss.

I tend to think of a sacrifice as a deliberate giving up of material in order to achieve some end. Here, the rook is a goner anyhow. But there is an "in between" situation - what Em. Lasker used to call the "desperado". This was an instance in which material is lost anyhow, so you give it up in a way that benefits your opponent least and yourself (relatively) the most. But here I wouldn't even call the rook a desperado. The fact is, there's not a blind thing Black could have done about it. All he can hope for is to achieve some counterplay whilst White takes the time to capture the rook. His prospects of even that much don't look bright.

Same thing isn't it. Reply: Yea, a sacrifce isnt really a a loss because you are getting something in return when you sacrifice (otherwise you wouldnt sacrifice). A loss is an unintential loss of something with no compensation.

Queen and rook to the bad...

White might have been wiser to have brought out his inactive pieces, e.g. Nf3 or Be2

u got lucky, if u were playing a better player. There's no chance of mate.

12...Bc5 13. Qxc7 Bf2#

White has all sorts of good ways to consolidate or trade down. The text move, at first sight, looks greedy, and might have been "punished" as in the comment above. White could instead have forced exchanges by 12.Ne7ch Bxe7 13.Qxe4, or better yet, 12.d3 Nc5 13.Nf6ch and 14.Nxg4. But it's possible White was displaying a particularly Byzantine cunning with the text move: 12.Qxa7!! Bc5 13.Qxc5 Nxc5 14.Nf6ch Kg7 ... when White's material advantage is reduced to a mere rook, 2 bishops and a pawn, but Black is left without the ghost of a chance.