3rd hand at this table. I have 50 hands with seat 3 at VPIP 45%/ passive and seat 5 is an unknown who has played every hand so far.

Should I keep betting or slow down here?

Full Tilt Poker $2/$4 Limit Stud $0.40 Ante - 6 players
The Official 2+2 Hand Converter Powered By DeucesCracked.com

3rd Street: (1.2 SB)
Seat 1: xx xx 7____Seat 1 calls____Seat 1 calls
Seat 2: xx xx J____Seat 2 folds
Seat 3: xx xx J____Seat 3 calls____Seat 3 calls
Seat 5: xx xx 7____Seat 5 completes____Seat 5 calls
Seat 6: xx xx 3____Seat 6 brings in for $0.50____Seat 6 folds
Hero: Q Q 7___Hero calls___Hero raises

4th Street: (9.45 SB) (4 players)
Seat 1: xx xx 7 6____Seat 1 calls
Seat 3: xx xx J 2____Seat 3 checks____Seat 3 calls
Seat 5: xx xx 7 4____Seat 5 checks____Seat 5 calls
Hero: Q Q 7 2___Hero bets

5th Street: (6.725 BB) (4 players)
Seat 1: xx xx 7 6 4____Seat 1 folds
Seat 3: xx xx J 2 A____Seat 3 checks____Seat 3 calls
Seat 5: xx xx 7 4 9____Seat 5 checks____Seat 5 calls
Hero: Q Q 7 2 J___Hero bets

6th Street: (9.725 BB) (3 players)
Seat 3: xx xx J 2 A 3____Seat 3 checks____Seat 3 calls
Seat 5: xx xx 7 4 9 3____Seat 5 checks____Seat 5 calls
Hero: Q Q 7 2 J 3___Hero bets

7th Street: (12.725 BB) (3 players)
Seat 3: xx xx J 2 A 3 xx____Seat 3 checks____Seat 3 folds
Seat 5: xx xx 7 4 9 3 xx____Seat 5 bets
Hero: Q Q 7 2 J 3 7___Hero calls

Complete on third. No need to get fancy here. Everything else looks fine. The river is definitely a call.