Originally posted by Fat Lady
You sacrifice does not look sound to me because you didn't have enough pieces readied for the attack. Your opponents king had lots of space around it and he had a couple of pieces nearby in a good position to defend, so you were unlikely to cause much damage with just your queen and knight.
You allowed the exchange of queens a few moves later. If you are ...[text shortened]... ding where you can swap off one of your last remaining pieces for his last pawn and get a draw.
Yes you are totally right on all counts. I guess really I was just rook hunting. And I knew the maxim that its better for the material advantage to exchange, which sharpens the power difference, but I did not know that its better to exchange pawns when down in material to try to get a draw, but I guess that makes a lot of sense.
Thanks for the pro-tip and the analysis, Fat Lady. Learning these basic concepts in chess is like hearing about gravity for the first time- its pretty obvious once you know it, and you easily intuit it, but its not really clear until its all stated so blatantly.