I Have Been Experiencing Lightheadedness (not Vertigo), Tingling In My

I have been experiencing lightheadedness (not vertigo), tingling in my arms, fatigue, and headaches for the last two months. I have been to several doctors, who have not been able to find anything wrong. I did have a balance test done by an audiologist, who stated that my left ear is not properly balanced with my right ear. I went on a cruise in the middle of November 2015 and a few weeks after the cruise is when I started to feel the above symptoms. My blood work came back pretty normal and my MRI came back fine. Can you assist?