World Health Organization: "Depression."; Mayo Clinic: "Depression."; American Psychiatric Association: "What Is Depression?"; Anxiety and Depression Association of America: "Understand the Facts: Depression."; Getty; Comstock Images;i Stock/Getty Images Plus; Thinkstock; AudioJungle; Rike; Vanessa Clara Ann Vokey; Somos/Veer; KatarzynaBialasiewicz; funduck

Everybody feels blue now and then, but most of the time it lasts just a few days and goes away on its own. Depression is different. It gets in the way of your daily life and makes it harder to do the things you love. You'll need treatment to get better.

Symptoms

There are a lot of signs of depression, but you may not have them all. How intense they are, and how long they last, are different from person to person.

Some of the ways you might feel are:

Sad, empty, or anxious. It will continue over time without getting better or going away.

Helpless, worthless, or guilty. You may feel bad about yourself or your life, or think a lot about losses or failures.

Hopeless. You may be pessimistic or believe that nothing good will ever happen. You may even think about suicide.

Irritable. You may get restless or more cranky than usual.

Less interest in activities. Hobbies or games you usually enjoy may not appeal to you. You may have little or no desire to eat or have sex.

Less energetic. You may feel extremely tired or think more slowly. Daily routines and tasks may seem too hard to manage.

Trouble concentrating. It could be tough to focus. Simple things like reading a newspaper or watching TV may be hard. You may have trouble remembering details. It might seem overwhelming to make a decision, whether it's big or small.

Changes in the way you sleep. You may wake up too early or have trouble falling asleep. The opposite can also happen. You may sleep much longer than usual.

Changes in appetite. You may overeat or not feel hungry. Depression often leads to weight gain or weight loss.

Aches and pains. You may have headaches, cramps, an upset stomach, or digestive problems.