Hello there Sir or madam, i have had these weird symptoms, two in the past month, when i slightly loose my peripheral vision. also, it becomes hard to focus on objects. then, i feel a huge pain in my head, on the sides and behind my eyes, and finally throw up. i was wondering if it was because of the heat because the second time this occurred i was playing soccer for 1 hour and 30 minuets but drank a gallon of water from my water cooler. however, the first time the symptoms came on a random day and i thought it was because i was wearing my 3D glasses. i was only concerned if it was a virus or just me working too hard.