The condition you suffered from is known as sudden sensorineural hearing loss. It's relatively a uncommon condition whose cause is many times unknown. This condition needs to be treated at the earliest
Next Steps
Though MRI is necessary it should not delay the onset of treatment. You need to be started on steroids and anti viral drugs as soon as diagnosis is confirmed by audiometry. Sometimes it may be good idea to give steroids directly behind your ear drum
Health Tips
Kindly Consult nearby ENT specialist for confirmation of diagnosis and appropriate treatment immediately