This is sooo normal. I take it this is your first child. Is he waking up on his own just looking around or is he waking up screaming like he is in pain? If he is just waking up being his happy normal self nothings wrong. He is just rested. Or maybe he is a little hungry not enough for a full meal but some milk or something a small snack just to be a little filling. His sleep patterns are going to change as he gets older. Wait til hes 2 and waking you up at 2:00a.m. saying "lets play mommy".