My son is 20 years old, a very good student, 6 3 200 pounds. He is having difficulty concentrating and is unusually lethargic. This has been going on for about 1 week. I noticed today that his fingertips are purplish, like when someone is cold. He had an auto accident about 4 weeks, and was briefly knocked unconscious. He had a CT scan on his head, and was all clear. Not sure if he is having middle of college blues or if there is msomething medically wrong with him. No history or any of these symptoms.