Your son sounds like he is having problems with his thought process, specifically and most likely hallucinations and delusions. He is also at an age where these types of symptoms often surface, called by some,first break symptoms of psychosis. These types of disorders can be treated but they are biochemical in nature and usually only medications work as a part of initial treatment.
He need to be seen as soon as possible by a medical professional at a hospital that has psychiatric facilities. The symptoms can often be controlled and they will also rule out any physical or substance related possibilities as well. But, he may get worse without treatment. This is considered an urgent situation and should not be delayed in terms of getting treatment. Steven