I've had hypoglycemic episodes and they feel absolutely terrible. Don't let it discourage you from running. Instead of drinking water before and after you run, drink gatorade for some carbs and eat a snack. Hopefully that will prevent it from happening again.
You have a full schedule of working and going to school and sometimes, esp with young women, the importance of nutrition is overlooked. When you said you "ate", what was it? A peanut? And what did your diet, including fluids, look like the day before? Dehydration is accumulative. Also, what kind of work do you do? If you, for instance, teach water aerobics in a humid, heated pool area, dehydration is possible in spite of all you drank.
I agree with LoriRD and lauragood - there's more info needed. The writer who suggested free radicals may be confusing them with electrolytes and fluid balance, but FR play no part in hydration.
I would love to know your weight, height and age.