Two Tournament Hands that I guess I played wrong

Am I playing this too tight here? Should I re-raise or not bother? Hard for me to tell if its the big stack picking up a pot because it was checked to him or if he has an Ace with a better kicker.

The second hand is the big hand. I pick up Kings and raise it 3x the blind. I get involved with another big stack at the table. An ace flops but so do all spades and I now have Kings plus the nut flush draw. I get raised on the flop, obviously with somebody representing an ace. I don't know what to do.

Table '11248462 86' Seat #7 is the button
Seat 1: cowboy88888 (5265 in chips)
Seat 2: thedude1832 (1540 in chips)
Seat 3: KnittenKitty (5250 in chips)
Seat 4: dace71 (1685 in chips)
Seat 5: <<69XX96>> (3112 in chips)
Seat 6: tbug91 (4020 in chips)
Seat 7: justinm11 (3019 in chips)
Seat 8: HERO (4929 in chips)
Seat 9: mizuno80 (2475 in chips)
FGators26: posts small blind 50
mizuno80: posts big blind 100
*** HOLE CARDS ***
Dealt to HERO [3d Ah]
cowboy88888: calls 100
thedude1832: folds
KnittenKitty: folds
dace71: folds
<<69XX96>>: folds
tbug91: calls 100
justinm11: folds
FGators26: calls 50
mizuno80: checks
*** FLOP *** [Ac 7c 5h]
FGators26: checks
mizuno80: checks
cowboy88888: bets 300
tbug91: folds
HERO: folds
mizuno80: folds
cowboy88888 collected 400 from pot
cowboy88888: doesn't show hand

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Level IV (50/100) - 2005/08/19 - 22:58:51 (ET)
Table '11248462 86' Seat #3 is the button
Seat 1: cowboy88888 (5365 in chips)
Seat 2: YesDear8 (5406 in chips)
Seat 3: KnittenKitty (4950 in chips)
Seat 4: dace71 (1785 in chips)
Seat 5: <<69XX96>> (3112 in chips)
Seat 6: tbug91 (3920 in chips)
Seat 7: justinm11 (3019 in chips)
Seat 8: FGators26 (7169 in chips)
Seat 9: mizuno80 (1975 in chips)
dace71: posts small blind 50
<<69XX96>>: posts big blind 100
*** HOLE CARDS ***
Dealt to HERO [Kd Ks]
tbug91: folds
justinm11: folds
HERO: raises 300 to 400
mizuno80: folds
cowboy88888: folds
YesDear8: folds
KnittenKitty: calls 400
dace71: folds
<<69XX96>>: folds
*** FLOP *** [4s 5s As]
FGators26: bets 500
KnittenKitty: raises 500 to 1000
FGators26: calls 500
*** TURN *** [4s 5s As] [Qh]
FGators26: checks
KnittenKitty: bets 1000
FGators26: calls 1000
*** RIVER *** [4s 5s As Qh] [Jc]
FGators26: checks
KnittenKitty: checks
*** SHOW DOWN ***

Should I have given the pot up on the turn. I guess I should have....Though he only bet the same that he did on the flop. So I was getting decent odds to hit my flush. Anything over 1,000 I'm mucking and moving on.