Hi B.. Yes, I would get him some help, especially if he can be helped before he enters Kindergarten. I suggest this so that from the start he is able to maintain control and be able to concentrate on his education. I have seen many children in our own school that go through the same issues and it is discruptive for the entire class, and very stressful. The other reason that I agree that you should get help is that he will get labeled as a troublemaker or disruptive and that will carry with him all through his school years. And then he won't have a chance!
I wonder...at home is he able to do his chores and activities on his own schedule or does he have to do them when you tell him? They may ask you this when you go for help.
We had to learn when our oldest was in pre school that pride should never come into play with our children, we had to get help for him and it was the best thing that we have ever done for him. He had a Concentration/Retaining Information problem...and because of the help that he received he was able to start kindergarten on the same level as his other classmates! We (as the parents) also had to be taught different ways to teach him or to work with him, it was great as a family!
I will pray for your family because I know that it is so hard to know where to turn!