From past 2 months I m feeling dizzy. I m fine if I don t exert myself. When I play snooker my neck posture is down and I feel dizzy and I m unable to play, as soon as I lie down I become fine. When I drive at night I feel dizzy when I see lights flashing on my eye and loud sound also makes me dizzy after a while, but again as I lie down I m alright. What should I do?