Your raise on 5th is reasonable and accomplished getting out the other low possible hand. 6th is questionable though. Villian makes 3 diamonds and 2 low, 7/4 to your 7/6. He has called all bets to this point, showing strength in one area at least. I'd back off here and hope to make either 2 pair or my low on 7th. Then check/call with apprehension. But No, I would not have called his river bet.

JMO - Knoll