When do I give this hand up

?
Full Tilt No-Limit Hold'em, $0.50 BB (2 handed)
Full Tilt Converter Tool from
FlopTurnRiver.com (Format: 2+2 Forums)
Button ($50)
Hero ($50)
Preflop: Hero is BB with J

, T

.
Button calls $0.25,
Hero raises to $2.25, Button calls $1.25.
Flop: ($4) 9

, Q

, 5
(2 players)
Hero bets $2.5, Button calls $2.50.
Turn: ($9) 9
(2 players)
Hero bets $6.5, Button calls $6.50.
River: ($22) 9
(2 players)
Final Pot: $22
I realized I didnt post how badly I played this river, I bet $15 here and folded to his shove, yay me

, but the question remains the same