It's a tough call here. Obviously, nobody but you is qualified to answer this. You can't take one situation and try to give advice. Only you know the types of hands this player is willing to call a raise with. Often times, if I decide to try and bluff at a pot, I will smooth call and hope that a scare card comes on the turn or river. He could have had a pocket pair that didn't improve or could have had a KQs or a hand that didn't hit. He could have taken your smooth calls as a sign of weakness and thought your showdown bet was a bluff, since you missed on the board. He could have made the raise to get you off of your hand worthy of only smooth calls. Or he could have flopped a monster and was waiting for you to improve. Good luck out there at the tables.