Two Pair vs Maniac

[ruapho]

Poker Room skin
Limit Holdem Ring game
Limit: $0.50/$1
9 players
Converter

Pre-flop: (9 players) Hero is MP1 with Q[img]/images/graemlins/spade.gif[/img] A[img]/images/graemlins/diamond.gif[/img]
2 folds, <font color="#cc0000">Hero raises</font>, 4 folds, SB calls, BB folds.

Flop: 6[img]/images/graemlins/club.gif[/img] A[img]/images/graemlins/club.gif[/img] 4[img]/images/graemlins/heart.gif[/img] (5SB, 2 players)
<font color="#cc0000">SB bets</font>, <font color="#cc0000">Hero raises</font>, <font color="#cc0000">SB 3-bets</font>, <font color="#cc0000">Hero caps</font>, SB calls.

Turn: T[img]/images/graemlins/spade.gif[/img] (6.5BB, 2 players)
<font color="#cc0000">SB bets</font>, <font color="#cc0000">Hero raises</font>, <font color="#cc0000">SB 3-bets</font>, Hero calls.

River: Q[img]/images/graemlins/diamond.gif[/img] (12.5BB, 2 players)
<font color="#cc0000">SB bets</font>, <font color="#cc0000">Hero raises</font>, <font color="#cc0000">SB 3-bets</font>, <font color="#cc0000">Hero caps</font>, SB calls.

Results:
Final pot: 20.5BB

I've seen SB capping streets with middlepair before. I thought he was with a weaker ace. When i made my two pair i was pretty sure to be good here, as i will beat A6,A4,A10. But did i overplay here, even vs a maniac ?