Yes, mine does that too. But I don't worry about it. I just set my system to never go to sleep, and it works fine.
Oh, almost forgot, you might want to stand or sit near to your Mac, and clap your hands very loudly, saying "time to wake up". I found this method of waking my brother very early in the morning to be quite effective, though, I usually stand in the doorway when I do it (fully clothed), for obvious reasons.