Went temporarily blind and everything i heard was in slow motion. what did i experience?

Fatal response: A vagal response, also called a vasogenic reaction or a vasovagal episode occurs when a stimulus like the sight of blood, a needle stick, a heat reaction or the fear of injury triggers the vagus nerve to slow heart rate. Symptoms include lightheaded, nausea, sweating, feeling very hot or cold, ringing in the ears and passing out are common. It is more common in young people.