If blood sugar levels become too low, hypoglycemia signs and symptoms can include: 
Looking pale
Shakiness
Sweating
Headache
Hunger or nausea
An irregular or fast heartbeat
Fatigue
Irritability or anxiety
Difficulty concentrating
Dizziness or lightheadedness
Tingling or numbness of the lips, tongue or cheek
 As hypoglycemia worsens, signs and symptoms can include: 
Confusion, unusual behavior or both, such as the inability to complete routine tasks
Loss of coordination
Slurred speech
Blurry vision or tunnel vision
Nightmares, if asleep
 Severe hypoglycemia may cause: 
Unresponsiveness (loss of consciousness)
Seizures
