Stress and fatigue often accompany one another. Fatigue is just one of the many symptoms of stress, and it also has its own signs and symptoms. Managing one may help you manage the other, but extreme stress is a subjective condition---it affects people in different ways, and closely monitoring your physical and emotional health is the only way to determine how you are responding.
Physical symptoms of stress include back pain, headaches and upset stomach, although other conditions may also cause these symptoms. Fatigue may cause common symptoms such as joint and muscle pain, sore throat and swollen lymph nodes.
Extreme stress and fatigue also have emotional effects including trouble concentrating or communicating with others. Decisions may seem more difficult and frustrating, and you may lose concern for physical appearance and other social matters.
Fatigue takes a mental toll, as well. You may be irritable or experience depression and memory loss.
Stress may cause panic or anxiety attacks. Temporary symptoms of a panic attack include a pounding heart and increased breathing, even to the point of hyperventilation. When you experience severe panic or anxiety, your body secretes cortisol, a powerful hormone. The excess cortisol typically passes following a bout of extreme stress, but when you are chronically stressed, the levels of cortisol in your body remain high. This can eventually affect your immune and nervous systems.
Fatigue is not only a condition, but also a symptom of stress. It is characterised by physical exhaustion and low energy, which can develop even if you are sleeping---feeling unrefreshed after sleeping is indicative of fatigue.
Despite what the Alfred Hitchcock thriller of the same name suggests, vertigo is not caused simply by heights---it is also a symptom of fatigue. Vertigo is the sensation that you or your surroundings are spinning.