TPTK reraise on paired river

[hockeyav]

PokerStars No-Limit Hold'em, $0.02 BB (7 handed) Hand History Converter Tool from FlopTurnRiver.com (Format: FlopTurnRiver)

Hero ($5.11)
SB ($5.08)
BB ($10.05)
UTG ($0.91)
MP1 ($2.73)
MP2 ($10.10)
CO ($2.93)

Preflop: Hero is Button with A, Q.
[color=#666666]1 fold</font>, MP1 calls $0.02, [color=#666666]1 fold</font>, CO calls $0.02, [color=#CC3333]Hero raises to $0.08</font>, [color=#666666]2 folds</font>, MP1 folds, CO calls $0.06.

Flop: ($0.21) 3, A, 7 [color=#0000FF](2 players)</font>
CO checks, [color=#CC3333]Hero bets $0.12</font>, CO calls $0.12.

Turn: ($0.45) 4 [color=#0000FF](2 players)</font>
CO checks, [color=#CC3333]Hero bets $0.32</font>, CO calls $0.32.

River: ($1.09) 4 [color=#0000FF](2 players)</font>
CO checks, [color=#CC3333]Hero bets $0.48</font>, [color=#CC3333]CO raises to $1.4</font>, Hero ?

What can I put villain on here? I haven't had enough action on him for any decent reads. I'm thinking I overbet on the turn when the 3rd diamond hit, or he could have been holding an A4.

Thoughts?