Head injuries are usually the most concealed injuries in existence. Not only are these injuries mostly invisible from the surface, they seldom inflict pain like all other injuries and can exhibit misleading symptoms such as Nausea, headache, vomit, etc. Although there are certain indicators to demonstrate the severity of a certain head injury, they are usually not the most accurate and reliable. Mild and moderate head injuries are the toughest to identify and the symptoms may take as much as 2 years to go away.