Too little
Stress, caffeine, screens, irregular schedule, noise, pain, sleep apnoea.
Too much
Poor-quality sleep, depression, thyroid problems, some medicines, or simply catching up.
See a doctor if the problem lasts weeks, or you snore loudly with daytime sleepiness.
This is general information, not a substitute for medical advice. If you have a medical condition, are pregnant, or take regular medication, talk to your doctor first.