A6s oop line check

[converted_hand][hand_history]PokerStars - $0.02 NL FAST (6 max) - Holdem - 6 players
Hand converted by Holdem Manager 3

BTN: $2.23 (111.5 bb)
SB: $1.07 (53.5 bb)
BB: $1.29 (64.5 bb)
UTG: $1.85 (92.5 bb)
Hero (MP): $2.00 (100 bb)
CO: $1.34 (67 bb)

SB posts $0.01, BB posts $0.02

Pre Flop: (pot: $0.03) Hero has 6♥ A♥
fold, Hero raises to $0.05, fold, BTN raises to $0.08, 2 folds, Hero calls $0.03

Flop: ($0.19, 2 players) 7♣ 9♥ 2♥
Hero checks, BTN bets $0.18, Hero calls $0.18

Turn: ($0.55, 2 players) A♠
Hero bets $0.16, BTN calls $0.16

River: ($0.87, 2 players) 2♠
Hero bets $0.25, BTN calls $0.25

Results: $1.37 pot ($0.06 rake)
Final Board: 7♣ 9♥ 2♥ A♠ 2♠

[/hand_history][/converted_hand]

What do you think about my line? Wasn't sure about my turn donk but expected some check behinds....