Problems with son

Its my first serious post here. I want to share with you with my emotions.

Recently I dont feel well. Im worried because of my son. Hes 18 years old and beeig so anxious. He is always doing something, talking very fast and loses temper very easly. He hadnt behaved like that before.  Im really worried. Recently we were arguing because he wanted buy a motorbike  I didnt allow him so finally he bought a motor bicycle (his picture on the left) . Hes so pround now and ridies so fast. Im so worried that he can have an accident :( I wonder, does he behave normal at his age? will he change? how can i help him? or maybe am i just too oversensitive?

I dunno...