Dog knows?

I love my baby toby he is an 8 month old chocolate lab. I wonder if he knows I'm pregnant because he won't leave me alone! He constantly has to follow me around, sit on the couch with me, usually has a paw on my leg, whines if somebody else has him and I leave the room. The only thing I can do without him is sleep! I love him but is he just attached or know something else is going on?