These are really great, especially for someone who is new to art.
But, I think Twilight's colors need a little more work; they seem to be a little too vibrant.
I do like the poses and ideas you used here, though.
I've done it maybe three times in my lifetime. I have no idea how to trigger them at will, though.
I do know that spinning your body does help in extending the dream; I've actually tried it at my last lucid dream a few months ago.