Call yourself a pro? Part 1

Here is one of my recent donkey plays. Would like some advice on playing it better if possible, or if you prefer you can just read it then shake your head in disbelief. That's what I've been doing after all....

Lapwai ($1/2 No Limit Hold'em)

The button is at seat 0.

Player1 posts the small blind of $1.
Hero posts the big blind of $2.
Player2: -- --
Player1: -- --
Hero: 4s 3d
Player3: -- --
Villain: -- --
Player4: -- --

Pre-flop:
Player3 calls. Villain calls.
Player4 calls. Player2 folds.
Player1 folds. Hero checks.

Flop (board: 4h 3c 8h):
Hero bets $9. Player3 folds. Villain
calls. Player4 folds.

4 players and the small blind means a $9 pot. So with bottom 2 pair, I lead out with a pot sized bet. I get one caller, so far so good. I'm thinking I'm against a bare flush draw here, or maybe something stronger like Ah3h.

Turn (board: 4h 3c 8h Kc):
Hero checks. Villain bets $17.
Hero raises to $50. Villain calls.

The turn doesn't complete the heart flush draw, and as I'm against an aggressive player, I decide to try a check-raise. He bets $17 into the $27 pot, and I raise it to $50, which he calls. I thought this was a big check-raise, but it still offered him 3-1 odds (calling $33 to win $95). Now I definitely know he's on a draw, as with a set or the unlikely top 2 pair, he would be re-raising me here. I now put him on KhQh along with Ah3h/Ah2h.

River (board: 4h 3c 8h Kc 7c):
Hero bets $50. Villain goes all-in for
$125. Hero calls.

The river card wasn't a scary one for me at first. I did recognise that it put a 3rd club on the board, but given that he'd called a pot bet on the flop didn't see him calling a pot bet and a turn check-raise with only an OESD, I put him instead on chasing the flush. As he was aggressive, I thought that he was pushing with a busted flush draw. So, I found myself calling his allin with bottom 2 pair, effectively ignoring the OESD that just came in for 65, along with the backdoor flush draw coming in for anyone with 2 Clubs. Unfortunately for me he had both, and picked up an extra 8 outs on the turn, which justified his call of the big check-raise.

Showdown:
Villain shows 6c 5c.
Villain has 6c 5c 3c Kc 7c: flush, king high.
Hero mucks cards.
(Hero has 4s 3d.)

Hand #49045855-21372 Summary:
Villain wins $373.50 with flush, king high.

My problem here was suspecting that the 7c may have helped my opponent, but betting anyway. Did I bet because I knew I would call the allin? Or was I betting to not get bluffed off? Regardless, I fired a bet and then convinced myself I was priced in for the call when he went allin, reinforcing my suspicions that the 7 was indeed a bad card for me. I should have had the discipline to bet then fold, or check fold unless the bet was really small. 65s should have been at the front of my mind, not the back, and that's what bugs me the most.

Live and learn with luck.... any comments? Other than "fold to the shove you donkey!!"?