Brief Answer:
Might be suffering from Viral Labyrinthitis or Menier's Disease

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

Looking at your symptoms,you might be suffering from two possibilities:
A.)Viral Labyrinthitis_Inflammation of the Organ of hearing and Equilibrium in the inner ear.It might be preceded by a viral infection in the respiratory tract like common cold.(In case of bacterial infection,you might be suffering from symptoms like pus discharge from ear or nose/fever,etc)

There is a more chance of viral infection in cold weather due to following reasons:
1.)During the winter, people spend more time indoors with the windows sealed, so they are more likely to breathe the same air as someone who has the flu and thus contract the virus
2.) Days are shorter during the winter, and lack of sunlight leads to low levels of vitamin D and melatonin, both of which require sunlight for their generation. This compromises our immune systems, which in turn decreases ability to fight the virus
3.)The virus may better in colder, drier climates, and therefore be able to infect more people
4.)The nasal lining which protects the nose from viral infection works more effectively during summer as compared to winter.

You may suffer from all the symptoms as described by you-reduced hearing,tinnitus,ear fullness,vertigo during this illness.After you get recovered from the illness,your hearing comes to normal but few patients might suffer from sensorineural hearing loss.

The initial treatment for viral labyrinthitis consists of bed rest and hydration.
You may get relief by taking medicines like Betahistine(like Zevert) and Benzodiazepines(like Diazepam,Chlordiazepoxide) during episodes of vertigo,which you are already taking.
Antivomiting like prochlorperazine if you are feeling nausea and vomiting and short course of oral steroids may help in severe cases.

B.) Menier's Disease-Meniere's disease is a disorder of the inner ear that causes recurrent episodes of vertigo, fluctuating hearing loss with a progressive, ultimately permanent loss of hearing, tinnitus and feeling of fullness or pressure in your ear as a result of abnormally large amounts of a fluid called endolymph collecting in the inner ear. In most cases, Meniere's disease affects only one ear.

There's no single test for Ménière's disease, and the condition can be difficult to distinguish from other conditions with similar symptoms.

The exact cause why Ménière’s disease starts is not yet known. Many theories have been proposed including: circulation problems, viral infection, allergies, an autoimmune reaction, migraine, and the possibility of a genetic connection.

Oncoming attacks are often preceded by an “aura,” or the specific set of warning symptoms, listed below. Paying attention to these warning symptoms can allow a person to move to a safe or more comfortable situation before an attack:
balance disturbance, dizziness, lightheadedness,headache, increased ear pressure,hearing loss or tinnitus increase,sound sensitivity,vague feeling of uneasiness,etc.

Attacks can last from 20 minutes to 24 hours. They can occur with the frequency of many attacks each week; or they can be separated by weeks, months, and even years.

Medicines helpful during Menier's disease attack are same as in viral labyrinthitis like Betahistine,Benzodiazepines,Steroids and Anti-nausea medicines. Along with these medicines,the use of diuretics is also helpful.
Avoiding trigger substances (eg, salt, chocolate, caffeine) is required. Smoking cessation also is recommended.

During an episode of vertigo, avoid things that can make your signs and symptoms worse, such as sudden movement, bright lights, watching television or reading.

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

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