One day I started feeling very light headed then I start sweating very bad all over my shirt was completely soaked. Then as I sat down in the car my vision started fading away with blackness. My vision went completely out and it was complete darkness. I turned to look at my friend who was sitting right next to me and couldn t see him. Then I attempted to look in the mirror to see if my eyes were doing something weird but I couldn t even see myself. Is this someting serious like life or death?