50NL - Set off flop, Quads on River, How do I play this?

I wanted to maximize my profit with this hand. He later told me he had QQ, and their was a K on board which killed me. I am sure if the K wasn't there he would have called/pushed and I would have been sitting pretty with most of his stack. Here's the hand. Was my river bet (which was the pot) too much? It hurt having two 5's out there because he probably thought I just had Trip 5's or something.

PokerStars Game #4489488294: Hold'em No Limit ($0.25/$0.50) - 2006/04/01 - 19:15:29 (ET)
Table 'Glaukos IV' 6-max Seat #6 is the button
Seat 1: blindside222 ($19.50 in chips)
Seat 2: sonix3 ($21.90 in chips)
Seat 3: PoFacile ($72.10 in chips)
Seat 4: vtforme ($13.80 in chips)
Seat 5: BrokeBack00 ($35.60 in chips)
Seat 6: johnnyBuz ($54.15 in chips)
blindside222: posts small blind $0.25
sonix3: posts big blind $0.50
*** HOLE CARDS ***
Dealt to johnnyBuz [5d 5h]
PoFacile: raises $1 to $1.50
vtforme: folds
BrokeBack00: folds
johnnyBuz: calls $1.50
blindside222: folds
sonix3: folds
*** FLOP *** [5c 4h Kh]
PoFacile: bets $2.50
johnnyBuz: calls $2.50
*** TURN *** [5c 4h Kh] [Jc]
PoFacile: bets $3
johnnyBuz: raises $3 to $6
PoFacile: calls $3
*** RIVER *** [5c 4h Kh Jc] [5s]
PoFacile: checks
johnnyBuz: bets $20
PoFacile said, "amazing how i suck tonight i have QQ"
PoFacile: folds
johnnyBuz collected $19.75 from pot
johnnyBuz: shows [5d 5h] (four of a kind, Fives)
*** SUMMARY ***
Total pot $20.75 | Rake $1
Board [5c 4h Kh Jc 5s]
Seat 1: blindside222 (small blind) folded before Flop
Seat 2: sonix3 (big blind) folded before Flop
Seat 3: PoFacile folded on the River
Seat 4: vtforme folded before Flop (didn't bet)
Seat 5: BrokeBack00 folded before Flop (didn't bet)
Seat 6: johnnyBuz (button) collected ($19.75)