What you describe, Magadalene, comes under the broader category in scientific terms of "sleep paralysis", which is attributed to a "gap" or delay between the mind waking and the body waking. In other words, you're still half asleep. We did an article on it in the magazine I run. While it explains the experiences for those who don't believe in the supernatural, I can't say I buy it. Fr. Gabriel Amorth tells us that demons are literally all around us and one would be foolish to think their influences extend only to vague mental temptations.
I've experienced similar to what you describe although it tends to be localized to a place rather than me personally. In our home, we've frequently had our names whispered loudly enough to jolt us out of sleep and yet this didn't happen when I was living away from home. In my other house (student house) I experienced something really weird: I was asleep and suddenly woke to feel tiny cold hands, like those of a child, grabbing at my hands and holding them so I couldn't move. I managed to drag my hands up to my Rosary, which I always wear round my neck when I sleep. As soon as I touched the Rosary, the hands stopped and when I switched on the light, of course nothing was there. I was convinced that I had been awake and not dreaming. The following morning, I told one of my housemates "You'll never believe what happened to me last night" and he replied that he'd had almost exactly the same thing, except that he couldn't move at all. :shocked: The student house we lived in had lots of problems- doors would slam and open again while we were all together in one room, and when we'd check, it was as though they'd never moved. We heard footsteps on the roof as if someone was in the attic and several times I felt a strong "presence" behind me when I was on my own. Neither the paralysis nor the whispering have been experienced in other locations though. I suspect our student house needed a good blessing!
While one is in a state of grace, demons have no power over the soul, that is true. However, I don't blame anyone who gets freaked out by it incidents like these! Our nuns at school were terrified of "ghostly" experiences and couldn't bear to hear stories of demonic manifestations.