gg is something you say when the game is over. Saying it during the game is a common taunt.
Was I rude?

You tell your opponent "good game" after the game is over. It is rude to say it during a game. Just like in an OTB tournament game, you are not allowed to talk unless its to offer/answer a draw, or say "adjust" But to tell your opponent "good game" while the game is ongoing? Rude, and you broke some rules.

I wouldn't have thought it rude, but I don't play blitz. In a normal game if you lose your queen for a knight, its doubtful you are going to win the game, unless it was your opponents intention, because he had a checkmate, or way he could win material back. In other words sacing his queen. However blitz is a horse of a different color.
Some prefer to play on, especially if it was just an oversight on their part, and they are good players, and don't necessarily need their queen to win games. However generally speaking the game is technically over at that point with some exceptions.
Added: A low time factor is one of those exceptions, also position of remaining pieces, and playing strenght of opponent.

Personally I would feel pretty annoyed at you also. With approximately 5 minutes left in the game, it is far from over (barring imminent checkmate) in a Blitz game. You were rubbing salt in his wounds.
I've had people message me mid-game to rub in victories. Some people just have no manners. My favourite being someone sending me "🌹🌹🌹" when it looked like he had a one move checkmate, not realising I had protection. Suffice it to say, the "🌹🌹🌹" was duly returned when I won the game a good 5 or so moves later.


Some people get upset to easily, even if his opponent thought it was rude. He also could have responded differently, and waited till after the game to do so. I wouldn't resign until I absolutely knew I was lost however, regardless of piece count. I've won many games that my opponents thought they had me. As the great Yogi said, It aint over, till its over. That means checkmate in chess.

so what you said was a little rude, yes...
but people on here are rude, all the time. no big deal.
in the future, you get people less upset if you say nothing. the only time I chat in chess if
- If its against a friend OR
- the other person speaks up first...

There are these people who wait till the last second to deliver checkmate. I was playing with this guy who had a mate in 1 and about 35 seconds left on the clock (in a 1 minute game). But he stopped moving, he was waiting for the last second to deliver checkmate.
Here's the twist, when he had around 5 seconds left on the clock, a message popped up saying that I won the game because my opponent abandoned the game. I said gg after that, he was very furious and went on ranting for the next five minutes, finally I had to close the chat.
Lol.

One time in a tournament I gave up my queen for a center pawn, lol. The guy was absolutely crushing me. He had 3 center pawns backed up by his queen and rook. Well, when I took his pawn with my queen the guy set straight up in his chair, because he couldn't believe it. Then he looked at me like he couldn't believe it. He went and got the TD, I'm not kidding, he was friends with him. They came back, and he sat back down, and then immediately took my queen with another pawn.
I retook that pawn with one of mine, and he retook it, with his final center pawn, then I began my attack, and I had a great position. I took that pawn with my knight forking his queen and rook, then he looked at me, and knew why I gave up my queen. I knew he would save his queen, and he did, and I took his rook, and he couldn't recapture it.
Not to mention I could keep attacking his queen. I ended up forking it, and his other rook as well. I won that game pretty easily. I wish I still had my old tournament book. I would load the game. That was probably one of my best games.
In a 10 min blitz game, I forked my opponents Queen and King - taking the king putting me +15. There was approx 5 minutes remaining.
At the start of the game we both wished each other good luck. After I forked the queen and waiting about 30 seconds for my opponents next move, I said "gg". He called me rude. I asked him why and he said it was arrogant of me to call Good Game while winning. While I certainly didn't mean it in a rude way and told him, he was clearly offended.
Did I break an etiquette rule by saying good game prior to his inevitable resignation?