If spooky phenomena are occurring whilst you are in bed, this might be a culprit. When asleep, our bodies are naturally paralysed (one theory being that this prevents us from physically ‘acting out’ our dreams). But under certain conditions consciousness can return before the body regains its capacity for movement.
In its semi-awake state, the mind reacts to awareness of physical paralysis with strange and unpleasant impressions. These commonly include a sense of ‘presence’ (usually malevolent, dangerous or weird); sensations of being held down or suffocated (often focused upon the chest area); and extremely vivid images of persons or creatures appearing to be the cause of these sensations. These images may be vivid enough to make those persons or creatures seem to have been physically present. Actually, they are the consequence of a known psycho-physiological process.