Sleep & energy
Why am i so tired all the time?
Puberty genuinely shifts your body clock later, so feeling wiped out is common at this age. Sleep, iron, food, stress and screen habits all contribute. Persistent exhaustion deserves a look-up rather than a shrug, because iron deficiency, thyroid problems and poor sleep are all treatable.
What this does and does not tell you
This is general information, not a diagnosis. Only a clinician can examine you, take your history and run tests. The same symptom has different causes in different people.
If something is sudden, severe, or getting worse quickly, get medical advice rather than reading on.