Checks like this are counter productive because they give black a free move. Better would be d4.

But did the knight move again? It had to be moved twice to get it where I wanted it.; Yes but I mean once I got it where I wanted it it stayed there.

Better is probably not to fianchetto, because white is looking at a pawn at e5. Better was probably d6, or maybe Re1 with the idea of d4. Maybe d4 is possible first. d4 exd4 Nxd4 Nxe4 Re1 looks good for white. So yes I'd play d4 probably.

Which side to castle on is totally based on the position on the board. Castling long here seems just fine to me, because it takes too long before black can castle short. Other than that, I would have preferred getting more pieces out and deciding later. Nf6 seems fine here.

You don't really want to attack the knight here. Yes, it gives black doubled pawns, but the d-file is half-open and with a rook on that file it can be quite usefull.

Because the e pawn will block black's DSB.

This is actually a very good move. I like it. It tries to attack the kingside without wasting time. That is usually the plan with opposite castling. Black did very well to move this pawn and waste no time. Playing Nf6 is also very good, but it may actually be better to already play this because black can do some serious damage over there.

Black would be fine with just Qxg5 here.

The second blunder because white simply loses the knight. Indeed Nf3 would have been best. The knight is used for defense too! So white lost a major defender. Also with the f and g pawn gone, white actually helped black. You will see this in the game later. The g and f files are wide open for the black rooks to attack the king.

It says -1 on the board yes. But white is down much more in reality.