Did I horribly mangle this hand? 10$ on stars

I've played alot more cash games then tournaments, but want to get better at tournies. I don't have too much experience near the end of big tournies, especially with a big stack. I had a real good chance to win my first big mtt today, but I think I might have blown it. Anyway today I was in a 10$ tourney on stars, with 850 entrants.

When this hand came up I was far and away the chip leader with 67k, when the average was ~12k. I had been playing very aggressively stealing blinds, when it was folded to me in the SB. The blinds were 400/800 with 50 ante, and the BB had 25k. I raised to 2000 with k/2 offsuit and he called. The flop was k/6/9 with 2 spades (i had none). I bet out 2000 and he raised me to 6400. I hadn't seen this guy play very aggressively at all, or seen any possible bluffs so should I have given this raise a lot of respect? Anyway I considered whether he might be bluffing an aggressive chip leader, or raising with a flush draw or some kind of pair, and I thought my kings were good so I raised to 14000. I think i read recently that blind play is a lot like heads-up, so folding top pair would be pretty weak (is this valid thinking or not?) Anyway he went allin for his last 10k, and I pretty much had to call getting 3:1 on my money. Turns out he had K/Q and had me outkicked. Losing this pot hurt a lot, now I think I could have folded to his flop raise and just continued stealing blinds with my huge stack, instead of playing a big pot? Anyway I went from dreaming of winning 2200$ to winning 35$...are tournaments always so frustrating [img]/images/graemlins/frown.gif[/img]