Flopped a flush. Tight player check raises turn?

[strunks]

UTG+2 is 19/3/1.75 over approx 1000 hands.

Ultimate Bet No-Limit Hold'em, $.50 BB (10 handed) FTR converter on zerodivide.cx

Button ($13.35)
SB ($57.45)
BB ($39.50)
UTG ($21.90)
UTG+1 ($22.30)
UTG+2 ($48)
MP1 ($38.05)
Hero ($105.70)
MP3 ($64.25)
CO ($31.30)

Preflop: Hero is MP2 with J[img]/images/graemlins/heart.gif[/img], 9[img]/images/graemlins/heart.gif[/img].
<font color="#666666">2 folds</font>, UTG+2 calls $0.50, <font color="#666666">1 fold</font>, Hero calls $0.50, <font color="#666666">4 folds</font>, BB checks.

Flop: ($1.75) K[img]/images/graemlins/heart.gif[/img], 2[img]/images/graemlins/heart.gif[/img], 5[img]/images/graemlins/heart.gif[/img] <font color="#0000FF">(3 players)</font>
BB checks, UTG+2 checks, <font color="#CC3333">Hero bets $1.75</font>, BB folds, UTG+2 calls $1.75.

Turn: ($5.25) 6[img]/images/graemlins/spade.gif[/img] <font color="#0000FF">(2 players)</font>
UTG+2 checks, <font color="#CC3333">Hero bets $4</font>, <font color="#CC3333">UTG+2 raises to $17.25</font>, Hero ???

Should I fear a bigger flush here since the opponent is a tight solid (aggressive post-flop, but not too aggressive) player? What are the other possibilities? Can it be anything else besides another flush?

Before that raise there I was pretty confident that my hand was best. Afterwards, I wasn't so sure.

Which is better: push or call hoping for a non-heart river?