What is wrong with my son?

My son is 3-year-old and 8 months already and barely speaks our vernacular at all. Does he have his own language? My hubby and I presume that he's just creating sounds which we couldn't be able to decode. Sometimes, he has his own world--he's staring at nowhere then giggles. Though, he can follow commands and loves arranging things in order, shapes and colors. Another thing I have observed, he does not want to look straight to my eyes when I wanted to talk to him. He would just stare at me then laugh.