Some of the symptoms of depression are a persistent sadness, anxious or “empty” mood. Sleeping too much or too little. Reduced appetite and weight loss or increased appetite and weight gain. Loss of interest or lack of pleasure in activities once enjoyed. Restlessness or irritability. Persistent physical symptoms that don’t respond to treatment (such as headaches, chronic pain, or digestive disorders. Difficulty concentrating, remembering or making decisions. Fatigue or loss of energy. Feeling guilty, hopeless or worthless.