Awake But Cant Move

This really scared me. Last Saturday after my graveyard shift (on Friday) I did not sleep right away when I got home. That makes me awake for more than 24 hours. After reviewing my son for his achievement test I decided to take a nap. I think its almost 7pm then, when all of a sudden I open my eyes and I cant move. I can see the whole room, my bed, the wall---, everything. I am lying on my side and it feels like someone is embracing me from my back causing me not to move. I tried to shout, I try to call my son David who was watching tv but no sound comes out of my mouth. I think it lasted for 2 or 3 minutes. I tried to shout several times and I can feel my heart pumping very fast. I thought I would not be able to wake up. I thought I would die. All of a sudden my son entered the room running because he got afraid of the halloween special of "Going Bulilit.", and that wakes me up. Though I am still sleepy I decided to go with him and watch television. It gives me a feeling of fear of sleeping again. 

I decided to google about this and find out that is called sleep paralysis. Its a state wherein you become conscious but your mind havent send a signal to your muscle to move since you are in a deep sleep where the whole body is relaxing. You can search online aobut sleep paralysis for more details. Thanks to the internet and I was able to remove my fear from this incident. I guess what I need to do next time is just to close my eyes again and wait until my brain completely restore its full functionality. But I still hope not to experience this again.