Depression is more than simply feeling unhappy or fed up for a few days. Most people go through periods of feeling down, but when you're depressed you feel persistently sad for weeks or months, rather than just a few days.

Anxiety is a feeling of unease, such as worry or fear, that can be mild or severe. Everyone has feelings of anxiety at some point in their life. Some people find it hard to control their worries. Their feelings of anxiety are more constant and can often affect their daily lives.

Social anxiety is more than shyness. It's a fear that does not go away and affects everyday activities, self confidence, relationships and work or school life. Many people occasionally worry about social situations, but someone with social anxiety feels overly worried before, during and after them.

Post-traumatic stress disorder (PTSD) is an anxiety disorder caused by very stressful, frightening or distressing events. Someone with PTSD often relives the traumatic event through nightmares and flashbacks, and may experience feelings of isolation, irritability and guilt.

Most people feel stressed sometimes and some people find stress helpful or even motivating. But if stress is affecting your life, therapy may be able to help.

If you have never received a diagnosis before or are unsure about how your difficulties might be labelled then Cognitive Behavioural Therapy might be a good place to start to begin to make sense of how you are feeling.