I'm having troubles with 77, 88, 99 when I don't plop a set. Opp is a weaker player and his flop bet seems weak.

1. Flop raise too weak right?
2. Given that he calls my plop raise and checks the turn, should I bet on the undercard?

***** Hand History for Game 3436728991 *****
$25 NL Texas Hold'em - Wednesday, January 25, 20:32:54 EDT 2006
Table Table 65173 (Real Money)
Seat 9 is the button
Total number of players : 10
Seat 1: infinti_cc ( $22.15 )
Seat 3: Torka ( $27.85 )
Seat 4: TEAMHONDA1 ( $38 )
Seat 5: TheChipGimp ( $30.55 )
Seat 6: cl188 ( $8.15 )
Seat 7: reddawgnc ( $21.45 )
Seat 8: pamajkl ( $6.80 )
Seat 9: makosiej ( $9.85 )
Seat 10: INABigPond ( $40.15 )
Seat 2: mjweinst ( $16.20 )
INABigPond posts small blind [$0.10].
infinti_cc posts big blind [$0.25].
** Dealing down cards **
Dealt to TheChipGimp [ 9s 9h ]
mjweinst calls [$0.25].
Torka folds.
TEAMHONDA1 folds.
TheChipGimp calls [$0.25].
cl188 folds.
reddawgnc folds.
pamajkl calls [$0.25].
makosiej folds.
INABigPond folds.
infinti_cc raises [$0.75].
mjweinst folds.
TheChipGimp calls [$0.75].
pamajkl folds.
** Dealing Flop ** [ Jc, Kc, 8d ]
infinti_cc bets [$1].
TheChipGimp raises [$3].
infinti_cc calls [$2].
** Dealing Turn ** [ 7h ]
infinti_cc checks.