What is happening when you have extremely low blood pressure.i have stomach cramps, diarherra , hot flashes then I get chills, vomiting and I have also fainted during these episodes. They last for about a day or two and then I start to feel ok again. When all this start to happen, because of the pain and discomfort I go to the emergency room, they usually give me drips, do blood work but never really pin point anything. It is here that I learn the t my blood pressure is extremely low.