There are a variety of anxiety disorders with varying symptoms. In order to describe the symptoms of anxiety disorders, one must look at each one separately.
There are five main anxiety disorders: panic disorder, obsessive-compulsive disorder, post-traumatic stress disorder, social anxiety disorder, and generalized anxiety disorder. Each one has some symptoms that are unique to that disorder, while all have some symptoms that are present in others. The best way to describe the symptoms of anxiety disorders is to take a look at the symptoms of each one separately.
Panic disorder revolves around the panic attacks one suffers from when they have this. Therefore, most of the symptoms revolve around the panic attacks. However, some symptoms are what happens in the meantime. Someone with panic disorder is usually terrified of having another panic attack. This is called anticipatory anxiety, a nervousness about the next panic attack. Symptoms of a panic attack can include a sudden feeling of doom, a feeling of being disconnected with reality, chest pain, trouble swallowing, shortness of breath, shaking, sweating, stomach pain, headache, tingling or numbness in the hands and/or feet, heart palpitations, nausea, and dizziness. Not everyone with panic attacks will feel all of these symptoms at the same time during a panic attack. It varies from person to person.
People with obsessive-compulsive disorder (OCD) have constant fears and thoughts and rituals. The constant fears are called obsessions and the rituals are compulsions. The obsessions trigger the anxiety symptoms and the compulsions temporarily soothe those anxieties. The rituals include things such as excessive hand washing or repeatedly locking doors. The symptoms include the need to constantly count things, check things or touch things. Oftentimes this includes a number such as locking a door three times. Someone with OCD will also have intrusive, disturbing thoughts such as ones that are sexual in nature, thoughts of harming someone they love, etc. Some with OCD also have a hoarding problem where they cannot throw things away. Many are obsessed with symmetry and order and this is usually visible in their homes.
Post-Traumatic Stress Disorder (PTSD)
In this case some sort of trauma occurs that triggers post-traumatic stress disorder. It first came about as a medical condition soldiers often had (and have) from war. Over time medical professionals realized that people with other traumatic events (rape, death of a loved one, accident, etc.) can also get PTSD. Symptoms include being startled easily, emotionally numb, irritable, aggressive, and even violent. Another symptom is flashbacks, which are memories of the trauma that come on during the day and in nightmares. Flashbacks can be triggered by anything that reminds the person of the traumatic event.
Social Anxiety Disorder
Social anxiety disorder is also known as social phobia. People with this anxiety disorder avoid social situations. The main symptom is worrying. They worry about what people will think of them, being embarrassed, and if people will notice that they are embarrassed. Those with social anxiety disorder fear being judged. They are excessively self-conscious. The disorder could evolve around one activity such as writing in front of others, or it could include all social situations. Symptoms include sweating, blushing, nausea, and shaking. People with social anxiety disorder also have anticipatory anxiety where they worry about social situations months, weeks and days in advance.
Generalized Anxiety Disorder
People with generalized anxiety disorder feel anxious and tense throughout the day even when there is nothing to worry about. They are often called "worriers" because they seem to worry about everything: money, career, family, etc. Symptoms include trouble sleeping, difficulty relaxing, difficulty concentrating, twitching, shaking, nausea, headaches, fatigue, difficulty swallowing, muscle aches, muscle tension, sweating, lightheadedness, feeling out of breath, hot flashes, and the need to use the restroom frequently.
It is easy to describe the symptoms of anxiety disorders, but any one of these can be a debilitating disorder. Each one is treatable. If you or someone you know has these symptoms talk to a doctor about it as soon as possible. The sooner the disorder is treated, the better.