Late diagnosis for my Teen

Good Morning,

I'm a single parent to my Lovely Boy I have found myself here after doing some research and wanted to join a community where I can speak to others in my situation.

My Son who is 15 has recently after a very long 4 years been diagnosed with Autism. I started the process when he had just joined yr 7 he is now in Yr 11 and leaves school in may, then he is hopefully off to start the next chapter in his life College, which I'm very anxious about for him new environments, new people and travelling out of the area etc....

I feel in limbo at the moment we've been given the diagnosis and now I feel like I am in a now what situation? I feel abit lost. I have told Son but he doesn't want to talk about it at the moment so I will respect his wishes. I know in time he will open up, Its always been something that has been in the back of his mind as over the years it has been lightly mentioned. 

Has anyone received a late diagnosis for their child? 

How has it been?