Why can’t I watch Inception without sleeping?

I want to see this movie, but I have fallen asleep everytime I’ve tried to watch it.  This is the first movie, since the Twilight movies that I can’t watch without falling asleep. (and I didn’t really want to watch sparkly vampires anyway)  So I put Inception into the PS3 tonight and 5 minutes in, the droning background score lulls me to a deep slumber.  Tomorrow night, I’m drinking a Redbull, a 5 hour energy drink and I will watch Inception all the way through finally for the first time in 5 tries.  I can do this…or is it all just a dream within a dream…