You're out of position and have to worry about any diamond hitting as well as be concerned about the board pairing, so I don't like your flop call of his raise. I probably 3-bet a little more than the minimum, to build the pot and regain the betting lead, and to keep my range better disguised. Calling pretty much polarizes your range to either a made flush or a good diamond draw.

By regaining the betting lead I can lead out on the turn for a normal 2/3 pot bet without giving away any more information on my hand, as opposed to checking to ihm and letting him control the size of the pot --since a check-raise by you at this point looks really strong and you'll lose any top pair or lesser hands with this play (from any reasonable opponent of course).