from time to time i have these episodes of fainting sweating blurred vision everything besomes very white and bright, i swear i can hear the ocean in my ears. sometimes i feel very nauseated. my body just feels very weak and my arms and legs feel very heavy. and this lasts anywhere from one minute to 30 minutes. afterwards i feel exhausted for almost a whole day. lately i have noticed a strange pain in my head just above my neck kind of like a hollow sort of pressure. i know this may sound crazy but can anyone even point me in the right direction as to what this may be?