Hi I recently stopped smoking and started exercising on a treadmill only on a walking program but i have not used it for the last four days as I feel really lightheaded this happened when I came off and I still have the motion feeling as if I am still on it, can you please explain why this is happening and should i stay off it or would it be ok to carry on. I am 49 and never really had to excerise before but the weight is creeping on. Please help, thank you.