Composition - I gotta tell you this looks like a combination of my last 2 flower shots (my ONLY 2 flower shots). The water is always great on flowers to show sharpness in my opinion. I'm going to guess this is a tulip too because of the textures on the petals, which is what my last challenge subject was, showing the same textures. The crease in the flower is a good idea, but I might not have taken this quite so close. Its a very nice combination of colors. I got ripped for not showing all 3 primary colors for my tulips photo, so I bet some of the people probably felt the same away about your entry too. I don't feel that way though. Its a quality composition.
Technical - I like the shallow DOF on this macro. The focus seems just a touch soft, but is pretty good for the most part. I think a little more contrast would help to provide a little separation between the flower and the background. The exposure is pretty good, if anything it might be just a touch dark. I can really appreciate you putting all the things you did to the photo in your comments section.
Overall - A pretty nice picture overall. It needs a little sharpening, a little more separation between the flower and the background and maybe not taken quite so close. Its a good photo, but doesn't have a real compelling element to push it up the next level (and if I could do this, I'd tell you how in a heartbeat). Good job and good luck in the future. - Bob