I was hoping white would play d3 to get some play in the center. But now he lost another piece.

Both the kingside and the queenside are very bad for white. Maybe white shouldn't castle anymore.

This is not a underestimating error, but a counting error. The pawn on d2 was defended three times.

Why with the king? It can be a target now.

I don't like this move. I would probably have played Rf8.

Putting the knight into the outpost is fine.

Why would you play this move? Givin away a free piece for nothing? White is going to equalise and is then ahead in development.

White has no clue what to play. He is just playing random at the moment. Though I have to admit I can't really find a good plan here. I would probably have played Bg2 because that bishop is doing nothing at the moment.

Black is not really attacking two pawns, really. Black is instead giving away a free pawn. Though there is something to say for it here. Black may want to try to push the queenside pawns and try to promote, since there is no rook protection on white's kingside. I don't think it is such a good idea. I would have played Qd7 to attack the a4 pawn, develop the queen and connect the rooks.

Took it with the right pawn too. Now Qc4+ looks nice. But still Bg2 to develop the bishop isn't such a bad idea either.

Bad move. It just gives away the pawn, resulting in a nasty check. I would rather have white here.