The egg in the lower right corner has a very bright and hard edge where the eggshell's edge meets the cavity, and it looks very 3D! That's exactly what I mean; if you apply more of those around your focal points or on materials that would just naturally be harder, your paint would have more life to it.
I love it! This is amazing. The pose of the dragon is incredible. It's like you know how the real dragon acts. You even drew his claws curled (I'm not sure the word is correct) to show that he just started.
Nice work! I love it that you picked it to be a white dragon with the waterfall in the background and all. The rainbow is a nice touch too. An interesting design for the dragonhead too: reminds me a bit of a bat... But why is the woman's mouth open? Is she screaming or what? It's the only odd part about this picture. Keep up the good work!