hey, ive had this happen four times in my life, all at random times, ive no clue what it could be but its very scary. first, my stomach starts hurting really bad, then i get sweats, then my ears get really hot, then i am barely able to walk, then my eyesight goes almost completey. this lasts for about 5 mins. what might it be? also the thing that usually helps is cold air from outside or a fan blowing on me..