Common causes of sleep disorders and feeling sleepy all the time: Stress. Concerns about work, school, health, finances, or family can keep your mind active at night, making it difficult to sleep. Stressful life events or trauma such as the death or illness of a loved one, divorce, or a job loss also may lead to insomnia and for more information visit:https://www.resmed.co.in/blogs/sleep-apnea