What Causes Lightheadedness And Red Dots On Body?

i really dont feel well at all. last 2 days i have been light headed and weak keep going hot and cold every time i drink or eat it comes back up till i have no fluids or food in my body. woke up this morning coverd head to toe in sweet. really weak. have noticed little red dots on my body all over so iam worried may have some think to do with this thanx Jay