Brief Answer:
Detailed evaluation is needed

Detailed Answer:

Hello,

Detailed evaluation is needed to find out the cause. The most probable causes are low blood pressure, low sodium level or diabetes. Consult a general practitioner and check your blood pressure level to check whether the BP is on lower side or not. Low blood pressure can cause similar symptoms and even hypertension can cause head ache.

Also, do basic blood investigation including electrolytes to check whether the sodium level is low or not. Hyponatremia( low blood sodium) can cause head ache dizziness. Also check your blood sugar level to make sure that the blood sugar level is well controlled. Do a CBC to rule it anemia.

The treatment will depend on the initial evaluation and as of now drink plenty of water to keep your self hydrated.

Wishing you good health. Thanks.

Regards

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