My Husband Is 77 This Morning He Overslept , That

My husband is 77 This morning he overslept , that is highly unusual for him. he still works a 40 hr a week job. He went to work but they sent him home . He got home and while talking on the phone fell asleep. I woke him up and hung up the phone. while I was talking to him he fell back to sleep. I woke him and told him to go to bed which he did. Do I need to worry?