When I get a lack of sleep (or especially multiple nights of bad sleep), I often have a splitting headache the next day that makes me unfunctional and worsens until I get more sleep. Other people I’m with have the exact same sleeping routines and never get any headaches, and can still function despite being tired. What’s wrong with me?
Different people need different amounts of sleep to function and be healthy, but you can’t “make up for the deficit”. If your body needs 8 hours per day and you sleep for 4 hours one night and 12 the next, your body doesn’t net it out. (Just using 8 hours as an example, it could be different)