There are many symptoms associated with the Seasonal Affective Disorder. People with SAD have many of the normal warning signs of depression. There are lots of symptoms but here are a list of three.
• Fatigue
• Greater appetite
• Greater need for sleep
If you experience any of these symptoms it is a good idea to get yourself checked out by a health professional because it could be this disorder or it also could be depression.
Source: http://www.webmd.com/depression/guide/seasonal-affective-disorder