Diziness - lightheadedness. To go for.

I was hospitalized on March 12, 2017 for having an allergy due to olfenac-p which got worsened when I was given injection of dexa which further caused me muscle weakness in thighs of both limbs. I also had breathlessness issue since the morning of March 12th. I was discharged from hospital on March 16th but still have the problem of breathlessness. I met ENT specialist today who suggested me city scan of nasal cavity. But I also have pain in the nerves in backside of neckline and for last 3 days I'm having dizziness lightheadedness and feel like going to faint. For this the specialist asked me to see orthopedic or neurologist. I want to MRI scan my head region to find exact cause of all this. Please suggest me which MRI I need to go for.