I can understand why this doesn't make sense to you. Here's what happened:

The guy with QQ had, for the third hand in a row, opened the pot for more than 6,000. He had grown to be a large stack over the last two hands by getting pocket JJs consecutively and having them hold up. So when he opened on the third straight hand with a big raise, the other guy thought he was just bullying the table. So he came over the top of the opener and moved all-in, figuring the opener would fold rather than risk his newly acquired chips. It turned out to be a horrible misjudgment.

That's why, in retrospect, I'm pretty sure that I would not have tripled up here. I had to act first, and if I had gone all-in, the guy with the queens would have moved to isolate me. I doubt the player with A9 would have come along because we had been playing together all night, and he knew that I would be playing something of solid value in this position where, if A9 was ahead at all, it wasn't much of an edge.

Thanks for all the comments. I know I made a really big mistake here. I keep seeing that K from the flop in my head all today! I'm sure I'll play this smarter next time.

Thanks for the explanation mxp. The actions of the other players do make more sense now. And you're right, you probably would not have tripled up since you were first to act.

Thinking about it, the guy with the QQ had kind of a fancy play there. That's his third wired paint hand in a row after two wins in a row. He probably wanted to look like he was bullying and was hoping someone would call him with a dominated hand.

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