Tails provide stability. Therefore, they should be able to move.
If that tail would move, it would either take the wings with it, or rip something.
It's hard to imagine this thing flying. The way the wings are connected to the tail just makes it look impractical.
Judging by the shading, there are quite some bones in the tip of the tail. Good job on making it look heavy. This does, however, make the legs look a little weak. In comparison, that is.
Would this dragon not simply collapse or fall back? It would need its hind legs in a different place, or a hell of a lot stronger.
Not a fan of the head, it's a little derpy.