text: Yes. As someone who's dealt with depression personally, I can tell you that depression is not just sadness. Depression can also cause irritability and mood swings. \n\n"Depression is a treatable illness involving an imbalance of brain chemicals called neurotransmitters. It is not a character flaw or a sign of personal weakness. You can’t make yourself well by trying to "snap out of it." Although it can run in families, you can’t catch it from someone else. The direct causes of the illness are unclear, however it is known that body chemistry can bring on a depressive disorder, due to experiencing a traumatic event, hormonal changes, altered health habits, the presence of another illness or substance abuse."\n\nSymptoms of Depression \n\nProlonged sadness or unexplained crying spells \nSignificant changes in appetite and sleep patterns \nIrritability, anger, worry, agitation, anxiety \nPessimism, indifference \nLoss of energy, persistent lethargy \nFeelings of guilt, worthlessness \nInability to concentrate, indecisiveness \nInability to take pleasure in former interests, social withdrawal \nUnexplained aches and pains \nRecurring thoughts of death or suicide