Whats wrong with me? Occasionally I will get a head-rush sensation, then my left eye will lose sight. Turn grey and last for couple minutes

See your PCP. Is this happening after you get up from sitting or laying. It can be a sudden drop in your blood pressure called orthostatic hypotension that is causing your symptoms. I would recommend seeing your family care dr for further eval.
Vascular. This sounds like a blood flow issue to me. You need to be evaluated immediately by your primary care doctor to see if you require imaging to look at your blood flow.