Tight-weak laydown of KQs?

[JustDerek]

I'm new to this site, so let me establish that my level of expertise at this point is probably something like "Advanced Beginner." In fact, I don't even know if I should have be playing $50 buy-in NL tournaments with 60-player fields, like the one a friend got me in on this last Saturday. Then again, maybe I do know enough to be dangerous.

I guess I can't can't kick myself too much for the hand I lost most of my stack on - I had AcKc, and the flop came Tc,Qc,Kd. In post-flop betting I was reraised all-in by a strong player 2 to my right. I had him covered by a little bit, and I called immediately. He turned over JhJs, so I was feeling OK about my chances. The turn was a rag... and the river was the frickin' Ts. Nothing I can do about a suck-out like that.

Anyway. The hand I was left thinking about most was not one of the ones I played, but rather one I mucked after my stack had taken its big hit and I was looking for a place to push all-in. The table was eight-handed. After getting nothing for several hands, I was in LP when I looked down at KdQd. I think, "OK, here it is," as UTG+1 limps in. Then the guy to her left (whom I've read as an experienced and VERY aggressive player) raises all-in. The girl to the raiser's left seems to be an average player; she deliberates briefly and then calls him. She's got him covered by about 1/4 of her stack.

[censored]. Now what? I'm pretty sure at least she's got a hand, if not both of them. I agonize within (but don't flinch on the outside, of course) for a couple of moments and then lay down my suited KQ. You probably know what's coming -- he had AT, she a middle pair, she took down the pot with a set, and I would have made a straight and tripled up if I'd stayed. Argh. Thoughts?