The fact that your son is 4 years old makes it more difficult to manage his levels compared to an adult like myself.
However, the fact that he was diagnosed last April is irrelevant. That was nearly a year ago now, and unfortunately, things won't magically become easier when he turns 5, 6, or 7 years old.
I realize this is a lot to handle and I can't imagine having a child with type 1, but there's a lot of evidence to suggest that the management of his diabetes is the problem rather than him having a rare form of type 1.
That may not be what you want to hear, but that would actually be BETTER in this case. It's easy to learn this stuff if you're willing to put in the time.