Symptoms of dizziness, fatigue and sleep disturbances are significantly linked with mental health impairments. 

Physical complaints are a common reason for visits to the family physician. A study of patients who complained of two or more symptoms including headache, dizziness, fatigue or weakness, palpitations and sleep disorders over one year showed primary care physicians identified only 6 of 29 patients (21%) whose responses revealed functional limitations due to emotional problems as suffering from an emotional disorder and only 6 of 23 patients (26%) with a lack of emotional well being were diagnosed with an emotional disorder. 
Non-specific physical symptoms may be clues to changes in emotional well-being. Improved recognition and recording of mental distress among patients who complain of these symptoms may enable better follow up and treatment. 

 Andre Matalon; Andy Kotliroff; Gari Blumberg; John Yaphe; Eliezer Kitai. Non-specific Symptoms as Clues to Changes in Emotional Well-being. BMC Family Practice. 2011;12(77)