Your lighting doesn't seem to bad considering you were using natural lighting the shadows look about right.
Your placement of the flower doesn't do any good. It needs to be out of the center and off to the side. I would crop in from the right side and a little off the top as well. Get rid of that green plant distraction.
You have a few hot pixels on the flower that need to be retouched as well. A simple repair would fix a lot with this photo.
would have liked a tighter crop, and maybe the flower off-center. you could get rid of the whole left side and bottom, and have a much better photo I think.