Hello.
Thanks for writing to us.

Extreme anger in children can be incidental or may be associated with bipolar disorder or ADHD.

Bleeding from nose after getting angry with severe headache means that the anger is causing a sudden rise in his blood pressure leading to nose bleeds and increased intracranial tension causing headache.
Such an anger may be pathological.

It needs to be treated with the help of behavioural therapy by a psychotherapist. You can also try to distract his attention whenever he is about to get angry. Anger control has to be learned after behavioural modifications.

I hope my answer and recommendations are adequate and helpful. Waiting for your further follow up queries if any.

Wishing you good health.
Regards.

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