Brief Answer:
All the symptoms might have started due to nasal blockage

Detailed Answer:
Hi,thank you for posting your query on health care magic.

I can undersand your concern.

You are suffering from congestion in nose,ear ache,throat pain and headache on right side.Allergy might be a cause.The reason that you are suffering all the symptoms on one side only might be as follows:
The right side of your nasal cavity might be narrower than left side, which might be due to deviated nasal septum.Allergy leads to swelling of the nasal lining.But if the right side of nasal cavity is narrower than left side,blockage would occur more on right side.Due to right sided nasal blockage,mucus secretions remain collected in the sinus leading to headache.Also eustachian tube blockage might occur on right side due to nasal blockage leading to negative middle ear pressure and ear pain(It is a tube connecting middle ear with the nose and is responsible for equalization of middle ear pressure with the outer atmospheric pressure).Also due to Right sided nasal blockage,nasal secretions are not able to pass outside through the nose,so they pass backwards,causing posterior nasal drip-this leads to irritation of throat leading to inflammation and throat pain.

You might find relief by taking following medicines :

Steroid Nasal spray like Mometasone-helps against allergy and reduces inflammation,
Oral Decongestant like Phenylephrine and Nasal decongestant drops like Xylometazoline-they help to decongest the nose and sinus cavity and helps in nasal blockage (if you are not suffering from Hypertension)
Antihistaminic like Levocetirizine-helps against Allergy,
Analgesic and Anti-inflammatory like Ibuprofen,
Antipyretic like Paracetamol, in case of fever
Antacid like Rantac -It helps against the increased acid formation in stomach due to the use of Analgesic and
Saline nasal spray-helps to moist the nasal cavity and removal of allergen particles from nose.

If you suffer from high grade fever or fever continuous for more than 2 days,pus discharge from nose,etc suggesting of secondary bacterial infection,then you might need to take oral Antibiotics after consulting an Otolaryngologist Doctor.

Also do steam inhalation. Do warm saline gargles. Avoid cold food.Drink lots of fluids(warm).
Exposure to smoke,dust, strong perfumes and scents, fumes, rapid changes in temperature, and outdoor pollution can be nonspecific triggers in patients with allergic rhinitis. Consider avoidance of these situations or triggers if they seem to aggravate symptoms.

Hope this answers your question.I would be happy to answer if you have any follow-up questions.

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