So Hungry

I'm not sure if this is related to the pregnancy since it's still so early, but I have been so hungry lately!  For the past three nights, right around 10:00, my stomach will growl and I'll feel like I could eat another full meal.  The other weird thing is that even though I'm so hungry late at night, I haven't been able to eat everything at dinner time.  Monday night I had a bowl of Special K cereal before bed, Tuesday I ate my Olive Garden left-overs, and tonight I had a giant mixing bowl full of air-popped popcorn.  This morning when I woke up early because I couldn't sleep, my stomach was growling and I had a protein shake and then a bowl of cereal.  Typically I just have one or the other.  I'm not going to restrict myself if I'm hungry, though.  It's just been kind of surprising.