Game drawn by stalemate.

Really?
I thought I was winning this one... I'm white...

You were.

So why did I get the message "Game drawn by stalemate."?

It was because black has no legal moves. Moving the pawn is impossible due to the pin, and the king cannot be moved due to the queens blocking off all the squares. This is what is called stalemate, and as such, the game is drew. Just a rule.

You were very lucky to get half a point. Look at move 17. Your opponent should have won the game easily. Also, after move 38 you had a checkmate in one move to end the game. 

Maybe try to focus more on checkmate patterns, especially when you have such a huge advantage at the end of the game. It can be easy to stalemate when one side has a lot of attacking pieces, but doesn't have a plan to end the game.

You should take the lessons. Why didn't you take the pawn?

The stalemated should win as it used to be some hundred years ago in England.

Chess would me much poorer without the brilliant stalemates. One could autopilot everything.

I agree with Bladerunner.  The side that gets stalemated should win, the person who did the stalemate should lose. Stalemating someone is a huge mistake, and although splitting the result with a tie is fair, I also think giving the win to the stalemated side is fair too. Sort of like pool. The opponent can be way behind and you only have one ball left to make, but if you scratch, all that huge advantage is for nothing, you still lose.

The rest of the game.

Don't worry about this. I hate Stalemate as well. Stupidest rule in chess by a mile. Zugzwang is a thing, so why should Stalemate be possible?

Ridiculous.

Well, there would be no subtleties in any endgame a pawn up. K and Harry, the h-pawn = simple win 

For those who hate the stalemate rule, there is a brilliant alternative game. It's called checkers.

A good trick to avoiding stalemate is to put your opponent in check every move.

https://www.chess.com/live/game/3474612005

That's tough!