25NL--Trying something out of character...suggestions?

[Abdullaev]

Villain is 42/0/0.6 over 38 hands. I have been playing only four tables and trying to raise twice as much as I normally do. At this point, my stats are something like 12/8/2, but my usual play is something more like 13/3/0.7.

UTG folds
UTG+1 folds
UTG+2 folds
MP folds
MP+1 folds
CO folds
Hero [$26.25] on button raises $0.75 to $1 with 6c 6d
Villain [$20] in SB calls
BB folds

Flop: [4d 3d 2h]

Villain checks
Hero bets $1.75
Villain raises $2.25 to $4
Hero calls $2.25

<font color="#666666">Hadn't seem him raise at all, preflop or postflop. Because he'd been so passive, I didn't think he'd raise a flush draw here. So I figured that if a diamond came on the turn I could bluff the pot. Plus I could hit my straight. Good plan? Bad plan? I rarely bluff at 25NL because of all the stations. </font>

Turn: 8c

Villain bets $3
Hero calls $3

<font color="#666666"> Now he's got 40% of his stack in there--$8 with only $12 behind. But his bet has decreased. Not sure if he doesn't want to overcommit or if he's trying to lure me into raising. So I just call, hoping for a five but trying to represent two diamond overs.</font>

River: Td

<font color="#666666">Jackpot . . . right? </font>

Villain bets $3
Hero raises $9 to $12

<font color="#666666"> I figured that this $3 bet screamed weakness, so I stayed in character and put him all in, even though he had more than half of his stack in already. Is this whole plan -EV? Suggestions? </font>