
Could he perhaps be startled (or recently have been startled) on waking? Something like the bin lorry, fire works, thunder or, in the home, like the boiler or dishwasher etc going on? He may have a negative association with something at the moment and he's worried and looking for reassurance. Have a think about routine events in and around the house which may have provoked a fear response, particularly if these could have happened when you were not around to reassure him. He's at a classic age for a secondary fear stage (or in my breed 5th fear stage out of about 25 LOL) so hopefully this is a temporary blip which you can identify the cause of and work gently round with him.
Other than the above, I'd think perhaps it might be best to have your vet check him over to be on the safe side.
regards, Teri