@Midlocats how's your baby doing?
This. My two cats have been sleeping for 3 hours now and they are fine But yes, if he stops eating, drinking, or using the box please go the the emergency vet, or if he becomes EXTREMELY lethargic you may want to go there too (this would be sleeping constantly, no longer walking around the house, no interest in anything at all).
Oh he's a handsome guy!! Since it's only been 2 hours, I'd chalk it up to his regularly scheduled nap. Keep an eye on him and if he stops eating, drinking, or using the box, then a trip to the ER vet is warranted.