I just returned from a trip in which I rode several rollercoasters, a monorail, and a ferry boat. While riding these rides I had no feelings of dizziness or motion-sickness, however for the last 2 days I have felt that my equilibrium is off, even when I sit. Mainly when I lower my head or look down. I have no nausea though. I also was taking medication last week, an antibiotic and a cough suppressant, as well as mucinex. I m wondering if what I m feeling is normal, and how long it should last.