I absolutely think you've done an amazing job! Your perspective is great and the only thing I think could be done to improve it is to maybe pull the tail down off the horizon line a little. Perhaps even adding a little boat for comparison to show how massive this creature is to add an element of horror. Another thing I noticed is that the water doesn't quite reflect the sky. Minor things, but I think they're the only things stopping me from believing it's a real photo at a quick glance. Even with those things in mind, I think you've done more than what many could do in such a short time, myself included. Keep up the great work!