fold now. turn and river obviously you have to bet. on the flop I think the range of hands that you can bluff out is kind of narrow. probably hes' not going to fold an ace, so you are trying to just bluff out a queen. on the river it looks pretty clear he had some sort of ace or queen diamonds and made the flush. nobody is going to try to bluff raise the river to rep the runner runner flush and he's almost certainly not going to value raise low flush.
River is an easy check/call because you have the 3* Nuts and in HU is enough.
I don't like bet OTR because he goes fold all hands that you win and raise all hands that you lose.
Pre 3bet is way too loose, flop/turn/river plays are fine (fold river). I can see some value vs sets, lower flushes and random J9 (AJ95/AJT9). River x/c is better vs. very aggro player.
