Brief Answer:
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Detailed Answer:
I read your question carefully and I understand your concern.

Judging from that description I wouldn't say there is reason to be alarmed. Usually when headache is related to brain lesions there are other signs such as weakness or numbness of the limbs on one side, double vision or vision abnormalities, seizures, trouble with balance and coordination etc. The feelings you mention in your legs, though it is a little vague, doesn't correspond to a brain lesion given it being on both legs.
Such headache as you describe is most commonly related to tension headache, the most common type of headache, often related to stress or anxiety. It usually responds to common anti-inflammatory painkillers like Ibuprofen.
Another explanation could be high blood pressure so that should be measured as well.

If the blood pressure is normal and symptoms do not correspond to pain killers though, then I would say some type of brain imaging is necessary. As I said it is unlikely it will reveal anything serious, but when there is a headache persisting over one week, in someone without a prior history of headache and without other explanations (such as high blood pressure, infections etc), then brain imaging is prudent even in the absence of other signs to exclude brain related causes such as a tumor.

I remain at your disposal for other questions.

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