The word depressed is a common everyday word. People might say "I'm depressed" when in fact they mean "I'm fed up because I've had a row, or failed an exam, or lost my job", etc. These ups and downs of life are common and normal. Most people recover quite quickly. With true depression, you have a low mood and other symptoms each day for at least two weeks. Symptoms can also become severe enough to interfere with normal day-to-day activities.
Many people know when they are depressed. However, some people do not realise when they are depressed. They may know that they are not right and are not functioning well but don't know why. Some people think that they have a physical illness - for example, if they lose weight.
There is a set of symptoms that are associated with depression and help to clarify the diagnosis. These are:
Many people with depression say that their symptoms are often worse first thing each day. Also, with depression, it is common to develop physical symptoms such as headaches, palpitations, chest pains and general aches. Some people consult a doctor at first because they have a physical symptom such as chest pains. They are concerned that they may have a physical problem such as a heart condition when it is actually due to depression. Depression is in fact quite a common cause of physical symptoms. But, the opposite (converse) is also true. That is, people with serious physical conditions are more likely than average to develop depression.
Some people with severe depression also develop delusions and/or hallucinations. These are called psychotic symptoms. A delusion is a false belief that a person has, and most people from the same culture would agree that it is wrong. For example, a belief that people are plotting to kill you or that there is a conspiracy about you. Hallucination means hearing, seeing, feeling, smelling, or tasting something that is not real.