Physical symptoms: 

Frequent stomachaches or headaches ; Complaints of nausea or dizziness ; Trouble falling or staying asleep at night ; Nightmares ; Fatigue or low energy despite proper rest

Behavioral signs: 

Tantrums ; Avoidance of certain places ; Fear of making mistakes ; Difficulty separating from caregivers ; A struggle with concentrating or staying focused

A family history of anxiety, bullying, academic pressure and exposure to neglect or trauma are all red flags. If you have tried calming techniques and are already limiting overexposure to stressors, a call to the pediatrician may be necessary