77 vs unknown WA/WB?

Just sat down. I would usually check raise the flop and lead turn. But how about this line? I'm really trying to rework everything right now and it seems I have a lot to learn.

Party Poker 3/6 Hold'em (6 max, 6 handed) FTR converter on zerodivide.cx

Preflop: Hero is MP with 7[img]/images/graemlins/spade.gif[/img], 7[img]/images/graemlins/diamond.gif[/img].
<font color="#666666">1 fold</font>, <font color="#CC3333">Hero raises</font>, <font color="#666666">1 fold</font>, <font color="#CC3333">Button 3-bets</font>, <font color="#666666">2 folds</font>, Hero calls.

Flop: (7.33 SB) J[img]/images/graemlins/diamond.gif[/img], J[img]/images/graemlins/club.gif[/img], 6[img]/images/graemlins/diamond.gif[/img] <font color="#0000FF">(2 players)</font>
Hero checks, <font color="#CC3333">Button bets</font>, Hero calls.

Turn: (4.66 BB) 5[img]/images/graemlins/diamond.gif[/img] <font color="#0000FF">(2 players)</font>
Hero checks, <font color="#CC3333">Button bets</font>, Hero calls.

River: (6.66 BB) 2[img]/images/graemlins/heart.gif[/img] <font color="#0000FF">(2 players)</font>
<font color="#CC3333">Hero bets</font>, Button calls.

Final Pot: 8.66 BB

Did I pick the right line, or do I only do this if there is an ace, king or queen out there?

I'm so lost. Thanks guys for giving me hope.