Within the past few weeks I've been getting very dizzy ( especially when standing up , but also while sitting down ) , and also , I'm not sure if this is part of the dizziness or not , but I've been sitting down , writing , and I would get the feeling that I'm writing with my left hand when I'm actually writing with my right hand ( which is my dominant hand ) . I've also been sitting in a chair , focusing on something , and I would see a shadow out of the corner of my eye , then then I would look over , there would be nothing there . My only specific medical history is ADHD , which I'm being treated for with the perscription Vyvanse . I don't eat anything between breakfast and dinner , ( almost 12 hours without food ) which gives me headaches from low blood sugar , but I've been on this medication for more than 6 months and I've never experienced anything like what I have been