I'm glad he's got diagnosed so early. I wasn't diagnosed untill I was almost 18. By that time I thought that I was a bad person because I thought, well, everybody's weird, so just must not be trying hard enough. I thought I was weak. Now I know I can do anything, just not the same way as everybody else.
I would pay very close attention to how he does things, try to learn how he thinks. As he get's older, he will have to learn how to act in an NT world, and you, as his mother, need to make a safe place for him to just be his ASD self. My father still has trouble accepting that I can't always talk about things when HE wants to or get right up and do house work, because I focus differently, and sometimes I'm just in the wrong gear for the job he wants me to do, if that makes sense. You're going to need to learn how to find roads you can drive in 2nd gear when everybody is driving to the same place in 5th. He's not going to have any idea, and it's not his fault. It's not yours either. Let me assure you that the more you come to know him, the more he will suprise you and show you beauty in places you never thought of before. Yah, it's going to be hard for all of you, I won't lie. But it will be worth it. Before I knew I was different, I knew I was blessed.
I would also suggest educating his teachers- the most trouble he will have in his life will be in school. He won't need nearly as much teaching in the classroom as he will on the playground, and teacher's don't realize that it's their job to do that as well. Supprisingly, kids accepted me more often than adults in school. I was "stuborn." IM me or e-mail me if you have any questions about what's it like to be autistic in public school. I have too many stories to type here. LOL.
Anyway, I hope you are now looking forward to the journey you have ahead of you.