Signs of poor sleep include feeling tired, irritable, and fatigued during the day, having difficulty focusing or remembering things, finding it difficult to get out of bed in the morning, feeling lethargic or drowsy in the afternoon, finding it challenging to stay awake in lectures, meetings, warm rooms, while driving or commuting, or after a heavy meal. Other signs include needing to take a nap during the day and needing to sleep late on weekends.