regarding the false-awakening and possibly darkness issue: when you become lucid.. close your eyes. and 'feel' around in the darkness on the 'ground' for objects... imagine gravel maybe. most of the time, for me, it turns out to be gravel, or ends up being the carpet in my dream room, random junk on the carpet, lol.
also, for darkness, sometimes it helps to "take off the sunglasses". that's worked for me once.