Strange way of going into a dream

For some reason, whenever I get in my dad's car, I feel pressure on my head and after a while feel tired and start yawning. I decided to experiment with that. Last night when I was in bed, I put my hand on my head and pressed lightly. I had some music going, and tried to wander my thoughts. I closed my eyes and was starting to dream slightly. My head felt really heavy. Suddenly I noticed my head was heavy and woke up instantly, even though I wasn't completely sleeping. I forgot what I had been thinking about completely and lost the feeling. It's a lot like Dream Boat's technique of staring at something. Someone should try it, see if they can get a lucid dream from it :) .