$21 NLTRN, AT on three-flush board

[RedNines]

This is the second hand of the match, so no reads.

Seat 1: HERO (1,510)
Seat 2: VILLAIN (1,490)
HERO posts the small blind of 10
VILLAIN posts the big blind of 20
The button is in seat #1
*** HOLE CARDS ***
Dealt to HERO [Tc Ad]
HERO raises to 60
VILLAIN calls 40
*** FLOP *** [Kh 4h Ah]
VILLAIN checks
HERO bets 100
VILLAIN calls 100 (really quick call)
*** TURN *** [Kh 4h Ah] [9d]
VILLAIN checks
HERO bets 200
VILLAIN raises to 400
HERO calls 200
*** RIVER *** [Kh 4h Ah 9d] [Ac]
VILLAIN bets 400 (insta-bet)
HERO calls 400

Comments on all streets. I was really lost on the turn and really had no clue if my line was good or not. I think the river is an automatic call since I'm getting almost 1:4.