Laughing In My Sleep

Ok, so this is (was) weird. I am totally positive I was laughing during my sleep-dream state this early, early morning. I can't remember the dream or anything about it really. I don't know even f it was actually a humorous dream or not. All I remember was that sometime during the night I awoke into that fuzzy state where you are half asleep and the brain isn't exactly alert just yet. I know I had been dreaming, but the details escape me, and I'm pretty sure I awoke into the fuzzy state of mine while I was laughing! So I am half asleep, half awake, and just cracking up at something. I never actually awoke at all. In fact, I just remember laughing, rolling over, and then falling back asleep again. This was certainly a first for me. Is this normal???