I can think of two things this might have been.

Sometimes in LDs I experience sleep pyralisis as a crushing weight and an inability to move. Maybe you were having a similar experience that your mind chose to interpret as contact from another being.

Or maybe you really were being contacted by some other being. I've had some pretty odd/amazing experiences in my dreams, so in no way am I going to pass judgement.

Sounds like a cool dream either way.