Hi drama_mama85
Welcome to PC! Yes, I know so much the frustration you are experiencing with your son. My son is now 9, but has been diagnosed ODD (Oppositional Defiant Disorder) since the age of 5. It is a mind boggling and overwhelming illness, and can drive one absolutely batty (battier for me).
I absolutely recommend therapy 200%. I also have a wonderful book called "1 2 3 Magic", which has been instrumental in keeping my son under control. He is well-behaved at school now, and excels in academics. Counseling is available on a sliding-fee scale in almost all cities, have you looked into that?
I wish you luck and peace.
Take care,
Dee