Hi,
Hypoglycemia unawareness refers to periods when blood sugar is low but you do not feel any different/have any symptoms at all. Even though you do not feel badly, this is more dangerous that when you become hypoglycemia with symptoms, because you have no warning--so you could continue to go low and pass out before you realize something is wrong.
It sounds like you had a
normalNormal saline flush hypoglycemic response and treated it, so I don't think this is your issue.
Be certain to check your blood sugars around times of exercise because many people with diabetes have drops in their sugars after/during exercise. And if you drive somewhere to exercise be sure to check your sugars before you start that car.
take care.