Hero 500 stack VERY tight image.

Hero UTG KKdT5d I raise to 7.5 I just want to build a small pot and I am not that afraid off being 3-bet since they will most likely expect me to 4-bet Also I dont want to limp call a raise to 15 or more. A tilted fish around 400 calls from btn and bb+sb calls‏.

Flop:KsJs6x 

sb bb x,x hero bet 20 into 30 pot. I dont want to x hoping the fish would bet. Although if he does hero calls and a safe card comes my hand is really deceptive? What do you Think is the right way to go building a pot or just x behind for x/r or safe turn?

All 3 Villians Calls Turn: Jx

sb bb x,x hero? What is the best way to extract value? I can x hoping the fish has Jx and goes bananas but at the same time he could check behind. The other 2 guys could have some draws so betting seems best? Result Hero bets 50 into 90 pot fish calls sb,bb folds‏.

River 8x My plan here was to do what a recently saw in a Tom Coldwell video on playing river OOP is to bet with the same sizing on the river as on the turn hoping he would smell that as weak and reraise. So hero bets 50 into 190 pot. Fish starts talking right away I have KK he also mentions if I have AA with missed draw but then decides just to call. I turn over and he shows me J674 for a fullhouse and I felt quite dumb for not stacking that donkey. Although took a mental note on him being SUPER loose pre and very tight after.

Did I missplay by not x the flop or the turn?