Opp is 22/10/2.0 over about 70 hands. Is this OK or is it spewing? When do you fire a second barrel when your flop c-bet is called?

PokerStars No-Limit Hold'em, $0.50 BB (7 handed) Hand History Converter Tool from FlopTurnRiver.com (Format: FlopTurnRiver)

MP2 ($50.25)
CO ($43.20)
Button ($46.25)
SB ($25.20)
BB ($57.50)
Hero ($50)
MP1 ($18.55)

Preflop: Hero is UTG with A, K.
Hero raises to $2, 5 folds, BB calls $1.50.

Flop: ($4.25) 8, 7, 7 (2 players)
BB checks, Hero bets $4, BB calls $4.

Turn: ($12.25) 3 (2 players)
BB checks, Hero bets $8