PokerStars No-Limit Hold'em, $0.50 BB (8 handed) Hand History Converter Tool from FlopTurnRiver.com (Format: FlopTurnRiver)

UTG+1 ($52.55)
MP1 ($49.50)
MP2 ($104.75)
CO ($11.80)
Button ($91.25)
Hero ($49.75)
BB ($43.80)
UTG ($60.05)

Preflop: Hero is SB with K, A.
4 folds, CO calls $0.50, 1 fold, Hero raises to $2.5, BB calls $2, CO folds.

Flop: ($5.50) K, A, 3 (2 players)
Hero bets $4, BB raises to $14, Hero ???

villain was 19/6/0.8, villain seemed tight.

Is this a standard push? I don't think we can fold this.