It's called sleep paralysis. It has been happening to me for years. The reason you can't breathe is because you panic when you realize that you can't move. Most people go through this at some time in their life, and there isn't much they can do medically to treat it. Here's a link if you want to read a little more on it.
http://en.wikipedia.org/wiki/Sleep_paralysis

id get my info somewhere besides wikipedia-its most unreliable especially not to be trusted with medical issues.

http://sleepdisorders.about.com/od/sleepparalysis/Sleep_Paralysis_All_About_Sleep_Paralysis.htm


look around on the internet instead of clicking on the first ting that pops up

but this site has a few dif. tings on it

DONT SLEEP ON YOUR BACK...LIE ON YOUR SIDE. THAT HAPPENED TO ME A LOT A WHILE BACK AND I SH1T MYSELF (NOT LITERALLY) I DECIDED TO STAY LYING ON MY SIDE AND IT STOPPED. IT WAS LIKE I WAS AWAKE BUT ASLEEP AT THE SAME TIME AND I COULDN'T WAKE UP OR MOVE..IT GOT TO THE POINT WERE I STARTED HAVING LIKE SOME SORT OF FIT TO SHAKE MYSELF OUT OF IT...I THOUGHT I WAS EPILEPTIC UNTIL I READ INTO IT MORE..IT WAS QUITE GOOD WHEN I GOT USED TO IT BUT A FEW SCAREY MOMENTS MADE ME THINK AGAIN ABOUT LYING ON MY BACK WHEN FALLING ASLEEP...ANYWAY I ONLY SNORE WHEN I LAY ON MY BACK..

omg ruuuuuuun

The Rodent Lives On, The Great White One.

It's called REM, it's a conmdition caused with sleeping

sorry let me correct my previous statemnent,REM sleep is when you wake up too early and your brain doesnt realize it and it takes a few moments to wake ur brain up

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irrelevant

Wow that happens to me too. I like to chill for a bit though when i realize i cant move. but then i start trying to move cause its freeky. OH try picturing yourself watching yourself sleep from the side of the bed, maybe your soul will pop out.

FUKK that happend to me once scared the shit outta me i couldnt move but i could hear things around me..

freeakkky

wow that was a lot of spam, and yeh try to remain calm when it happens, it helps