I really enjoy this photograph. Its clean, its crisp and simple. And well, just over all very appealing.
The blue and pink contrast is perfect. And its not so contrasted that it hurts the eyes. The blurred background with the other pink cosmos in the back makes the photo a lot more interesting then if you had chosen to have the only the sky or a bush as the background instead.
I have a problem with watermarks that take up an unnecessary amount of space, unless totally needed. Your watermark though, is very simple and subtle and doesn't draw the eye away from the actual photograph.
So overall I really don't see anything wrong with this photo and I find it a very simple yet beautiful photograph!
I find it hard to make a critism, so I leave it with just a comment. Mostly because i dont photograph myself (well just for fun, but nothing serious), but i do hope my comment can be helpfull.
First of all, i responded because i drew a cosmos flower myself so i know the beauty of this flower indeed. Its a simple but very nice flower to watch (lol complex when you try and draw it). What i like about this flower, is that you tried to show it beauty without exaggerating. I mean you could have photographed the flower so you look inside of it more.. But i actually like it like this, as it is. Like i said, its not over-the-top, but it is beautyful and leaves you up for imagination. What i like about the background are the faded Cosmos flowers you can't really see but they are still there. The light is good, the picture is nice and sharp too, i like that.
As for critism, i am afraid i dont have something i would or could recommend. As i said, i don't know much about photography. At least not enough to help you out. I can only say what i like about this picture ^^ but I'm sure it made you happy nontheless. Hopefully, this comment is useful to get better ^^