Look up a good book on mediumship. The hand thing and now this, it seems to me a spirit is trying to use you as a medium. That heavy feeling at your back is a spirit trying to impress its energy. If it succeeds, you're head will feel tingly and heavier. I don't personally believe in letting just any spirit use someone else as a medium like that. Use automatic writing and see what he wants or make a pendulum and try that first.
Here is a good source on pendulums