Well that is nuts!! How perfect is that...that you are in a 13-year Red Serpent phase and you dream of this SNAKE (serpent) that is being Transformed from the inside out! Woah baby woah!
To me the snake is symbolic of transformation and kundalini energy that moves up your spine.
You are growing and transforming, Leah! (just look at that snake! wild)
I like that: you were to do hard work, basically - with a shovel! This means that it will take some hard work on your part but you will dig deep into yourself and turn over some inner 'darkness' to see what's under/in there! Shed some Light on the subject, basically! EnLIGHTen your Self. Cool.
When I read your dream again it makes me feel like you HAVE grown & transformed a huge huge huge amount in a very small amount of time...I love it that the man patted the snake and told it was good! Yay! You're getting accolades from an aspect of yourself - the Authority within - that's fantastic that you have a good relationship with your inner Authority! Good one....