Yes, don't waste time with counselors or family doctors. I took my son to two different cousnelors and really it was of no help honestly. Both had different opinions than the psychiatrist did and my pediatrician showed no interest in talking with the counselor. Ask around or ask your family doctor who is a good child psychiatrist, you want one that is conservative with medications and one that really evaluates the child, not just whips out a prescription pad and prescribes every drug in the book. Also, how does your son do in school, is he in any type of daycare setting, etc? Do you think he means he will kill you or do you think he's just saying it. I think a lot of kids say things like that for shock value. Also, when you say he hurt you, give an example. I wish you the best of luck, it sounds like a VERY tough situation!
Being his mother, it was hard for you to say that he wanted to kill you.Since his actions go well beyond difficult behavior, I would have him evaluated, as soon as possible, by a pediatric psychiatrist. Don't waste your time with a family doctor or a pediatrician. They do not have the training to help you and your son.
To me this sounds like something different from ADHD. I would go see a child psychiatrist and see what they say. He is young for medications. I'm really sorry you are going through this, sound horrible, you cannot even feel safe sleeping. Does he not sleep for days on end? How much does he sleep during hte night hours. Be sure to mention that to the doctor. I am really sorry.