Brief Answer:
Possible upper airway infection

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

Since the headaches have been going on beyond the usual duration of common primary headaches like migraine or tension type headache then a specific cause must be suspected. The fact they are located on one side with ear symptoms supports that as well.

One possible cause could be a middle ear infection which could justify an unilateral headache as well as the blocked ear.

Another possible cause could be an upper airway infection which can lead to sinusitis with pain in the eye area as well as obstruction of the Eustachian tube, a canal which connects the middle ear with the back of the throat leading to fluid accumulation in the middle ear. If you also had flu like nasal congestion and discharge in the past few weeks I would say this is the most probable cause.

So a visit to your primary physician or an ENT (ear-nose-throat) specialist is the recommended next step to check for signs of infection and if confirmed decongestants and at times antibiotics might be required.

I remain at your disposal for other questions.

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Brief Answer:
Read below.

Detailed Answer:
Thank you for the update.

Panadol is a medicine aimed at relieving pain, so it is not supposed to do much about light-headedness.

The causes of light-headedness may be so many, the list is really long. At times may be a transitory thing related to lack of sleep, not eating, caffeine or other stimulants, stress etc. If it's a persistent problem though even with a regular lifestyle then some tests are advisable to search for some common causes such as infection, heart abnormal rhythm, metabolic or hormonal alterations etc.
Such tests include complete blood count, erythrocyte sedimentation rate, c-reactive protein, glucose, kidney and liver function, thyroid function, electrolyte panel, EKG, blood pressure measurement.

I hope to have been of help.

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