This depends on your opponent, if he is a loose fishy player, your raise is ok coz he could have any K. Against a tight player, Id call, as he`ll fold most of the hands that you beat, probably only calling with AK (which he would have 3bet preflop) or AJ which splits the pot.

Although you were super unlucky in this hand I feel that raising the river was a mistake. This second King on board in my eyes is very scary given the fact you were getting called right through. He called your raise so 66/1010/QQ/K10/QK Are a very easy possibility KK as well but who can put someone on Quads right. I think that only if the board didnt pair and no diomond came as well then raising would be an option. Very unlucky though.
I get a little frustrated with these types of hands because even though you turned the world he was never folding.

Where did it went wrong? or just a unlucky river card...!