Is my dog mad?

Help! Alfie's doing weird things. Well, they may not be weird, but they are to me, as I've never had a dog before. In the last couple of days, he's started mistaking my couch for a flower border. He'll be happily snoring on his blanket, when he'll suddenly get up, and start digging at the couch, as if he's trying to unearth a long-lost bone. Is this a normal dog thing? A Cavalier King Charles thing? What does it mean?