Thanks for your query.
Allergic reactions do not last for 2 years!
From the description of symptoms, you are suffering from either, a disorder of the internal ear which is responsible for maintenance of balance; or, a benign condition called BPPV (benign Paroxysmal Positional Vertigo
I therefore suggest that you consult your ENT specialist
, who will subject you to certain tests and prescribe appropriate treatment accordingly.
Dr. Rakesh Karanwal