Hey Kostas,
Because the truck was so bold blue in color.....it actually competes with the flowers. I like how you got the stem and the main bloom and bud and bloom to the right don't bother me but the flower behind the main bloom does. I would have picked it out in the field.....because it is yours....but now I would take the time and remove the 2 petals sticking up above the main flower. Light looks pretty good but perhaps a bit more contrast on just the flowers to make them pop and stand out from the BG. Minor tweaks will take this up a notch.
Hi Kostas. This first thing that hits me about this image is the BLUE! Your flower is very colorful and nicely photographed, but it is being overpowered by the background - I would suggest selecting the blue and desaturating it to the point that our attention can more easily focus on the flower itself. Roman makes an interesting point about the two petals behind the main flower that you may want to consider, but it's a minor issue for me. Overall, I think taming the background will take this image up a couple notches.
I agree with the men here but I have to say if I was a young girl I'd want this on a big poster hanging on my wall - I love those highly saturated colors!