I have been feeling giddiness from about 18 months. I feel this when I speak loador jog or walk fast. It is causing me a lot of problems. I am not able to concentrate and I left my job due to this reason. When I checked with the doctor they told me I do not have any problem. They checked my entire nerve system, ear system, blood check up, thyroid checkup. I do not know whether I have any problem with my brain because 18 months back I had felt some kind of a pain in my head for about 1-2 minutes. After that the giddiness started. Please help. Thanks.