What does it mean when you are nearly asleep and some kind of pressure is pushing you downwards?
When we “fall” asleep, our life force (“prana,” “chi“) withdraws from the outer periphery of the body, from the senses, nerves and so forth. We enter the state of subconsciousness. In the yogic teachings, this lower state of awareness is “lower” both in the brain and in the astral body’s “lower” chakras. Hence the instinctive language we use is to “fall” asleep. Thus, it would not, therefore, be surprising for you to experience being “nearly asleep” as a sensation of going downwards.
Paramhansa Yogananda taught that in sleep our consciousness resides in the lower chakras. This is not so simply translated into our actual experience, in part because we are, well, asleep! Nonetheless, the sense of lower or downward is very much connected with subconscious states.
I would conclude that unless you have a dread, fear, or sense of some other “entity” attempting to gain control of your consciousness, that you are simply experiencing the process of drifting off to sleep and into the subconscious state. The fact that other people, perhaps even most other people, do not experience this or are unaware of it (because “falling” asleep), or express it differently doesn’t negate your experience of the same.
It is very typical and the cause of a certain amount of insomnia or persistent delay in achieving sleep that some people have an innate resistance or fear of sleep. There can be innumerable reasons for this but let us say, existentially speaking, simply that there can be the fear of loss of consciousness or loss of self-awareness when sleep overcomes one. I don’t necessarily sense this in your question but it is at least possible.
Traditional prayers before sleep; the counsel to offer back to God one’s life, possessions, talents, etc., before sleep — such acts, apart from their spiritual benefit and affirmation of deep truths, can act as a comfort to one who has an innate resistance to sleep (for whatever reason). Okay?
Be well, be happy, be thankful!
Seattle WA USA