I have been trying to astral project for a while.
This may sound kind of weird, but i get a numbing feeling in my legs. I focus on that feeling and the rest of my body goes numb. I try to lift out of my body. As I'm lifting my physical body was also lifting, My back started to arch creating something almost like a loss of connection.
As I was floating away, I noticed my physical body was arching and accidentally went back down.
Was this a connection to the astral plane?
Possibly. I'm more inclined (being something of a skeptic) to think you actually weren't as disconnected as you thought and you just have really good powers of envisioning what you want. Just remember: the journey is more important than the destination. Absorb everything you can at the point you are. The next step will come.