 [ Symptoms ] my 13 year old son feels angry and cries in the evening sometimes and does not know why what could cause this  he is fine all day and then he cries in the late evening sometimes he says he feels very angry and he has no idea why he feels this way i have explored the possibility of low blood sugar and that may be the cause but i am wondering what other things may cause such a reaction [ Disease ] black eyes may or may not be associated with a concussion a blunt injury to the forehead resulting in a bump is really an accumulation of blood under the skin because of gravity and the fact that we walk upright this accumulated pocket of blood can gradually drain downward toward the eyelids and upper face and give a person black eyes