Brief Answer:
These symptoms indicate sinus related problems like sinusitis.

Detailed Answer:
Hello Madam
Welcome to Health care Magic

I am Dr. Dadapeer K, an ophthalmologist and I answer health problems related to eye.

I reviewed your history.
These symptoms of irritation behind the right eye with sense of pressure in the forehead and cheeks typically worsening on lying down indicate sinus related problem because of sinusitis.

The irritation behind the eye is because of referred pain.
Hence your thoughts are correct and this requires treatment for sinusitis by the use of antibiotics, anti-inflammatory drugs...

Hence I advice you to consult your primary care physician or ENT doctor for evaluation and treatment accordingly.

Hope this information is helpful to you.

Thank you

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