My throat has felt tight for the past couple of years. Only on the left side. When I get sick and a sore throat occurs only the left side is sore.?

???? Have you seen an ENT or GI for a scope to look into the throat and surrounding tissues? If not, do so. If you have, then you need to get a ct scan of the soft tissues of your neck. Don't hesitate and wait. This could be serious.
ENT doctor. Agree with Dr. M. Your symptoms suggest an anatomical anomaly that may be making one side of your throat more susceptible to infections. If may be useful to consult an ENT doctor.