I understand the frustration at the weak little bets on the flop, but I think the move here is to just call the flop. You have 2 overs and 2 decent redraws, if someone gives you 19:1 pot odds just take it.

From the rest of the hand, my best guess is that he had AXh, put you on an 8 until you checked the turn and river and figured you were bluffing and would fold - or a high was good.

I have seen $50NL players here turn up with REALLY good hands on the river (K8, J9) and I just laugh at their pitiful extraction ability.