i think everyone has experienced this at time or another in life, it's called sleep paralysis, learn as much as you can about it, to overcome the
fear of it.
Yes sleep paralysis, can be a very scary experience. Last year I would get this everynight. It turns out alot of medications can cause this to
happen. For me it was Xanax. Needless to say I stop taking it.
Sleep paralysis usually comes and goes for most people. It depends on stress level, medications the person is taking, and I've even heard the length
of sleep. If this is a repeated experience for you then consult some kind of doctor.