was it the wrong play or just bad timing?

I play in a free poker league in ND and recently won a trip to play at the Bay 101. We started the day with 10,000 in chips. After about 4 1/2 hours i had built my stack to about 45,000 ( I was feeling good at this point ) Here is where my question comes in.... I get moved to a new table with the blinds 250/500 50 ante I get dealt KK im second to act preflop. UTG limps in so i raise it up to 3000 ..Folds around to UTG who reraises me to 7000. I think for a min then call the other 4000.. the flop comes 10 3 6 and UTG bets out 10,000... I go into the tank.. While I havent been at the table long and the only hands i have seen the guy play hes been forced to show only once when he flopped top pr with top kicker.. So with a lil over 25,000 in the pot already I put him on maybe A 10, possibly K 10, QQ, or Jacks. So feeling like I still have the best hand and not wanting him to draw out I move allin.. He quickly calls (which when he called so fast i knew he had the one hand that would be ahead of me preflop.) YUP he shows his Aces and having me covered by a mere 3400 I am out of the tourney. Now was that a bad play or just bad timing. BTW also at this point if i had won the hand it would have made me the tourney chip leader

Really hard to through Ks away especially with no A, and no obvious straight or flush on the board. Maybe since you didn't know the player and he had you out stacked it would have been prudent to fold, but then again...nah definitely call you will win more in the long run then loose.

The limp re-raise against your large 6x BB pre-flop raise should have set off warning bells.
However, this is just a cold deck situation. It is almost impossible to get away from KK's with that board. Even Dan Harrington in HOH says that he can't get away from KK's when he's up against AA's.
I think the only thing that may have saved you would have been a smaller pre-flop raise. Then the rest of the betting would have been based upon a smaller pot. But even with that, you still would have probably gotten all your money in by the river.
Unfortunately seems like just bad timing.