400NL - KK, I lay down my overpair with 3:1

[Mat]

How bad is this ?

Villain is a 20/13 (92 hands), not tricky and kinda nit player. I'm very aggressive in the blinds, especially when I'm HU vs a nit, though I don't think he has adjusted his game much because he hasn't been 3-betting me a lot or being aggressive with his draws or marginal holdings.


EverestPoker Game #1746781076: Table Bamako-5 - $2.00/$4.00 - No Limit Hold'em - 19:16:19 - 2007/07/01
Seat 1: Hero ($435.30)
Seat 2: i_will_bluff ($392.00)
Seat 3: skyblues ($382.00)
Seat 4: Kaffedopp ($437.00)
Seat 5: kceler ($422.00)
Seat 6: don@david ($132.50)
Hero posts the small blind of $2.00
i_will_bluff posts the big blind of $4.00
The button is in seat #6
*** HOLE CARDS ***
Dealt to Hero [K[img]/images/graemlins/diamond.gif[/img] K[img]/images/graemlins/club.gif[/img]]
skyblues folds
Kaffedopp folds
kceler folds
don@david folds
Hero raises to $12.00
i_will_bluff raises to $36.00
Hero calls $24.00
*** FLOP *** [J[img]/images/graemlins/heart.gif[/img] 9[img]/images/graemlins/diamond.gif[/img] 5[img]/images/graemlins/heart.gif[/img]]
Hero checks
i_will_bluff bets $45.00
Hero raises to $150.00
i_will_bluff raises to $356.00 and is all-in
Hero folds


Thoughts on all streets are welcome (4-bet pf ?).