Chris, my son went through the same thing, he seemed to be doing fine on the low doses but the blood work always seemed to say no you are not.  One doctor in particular is always wanting to raise the meds and it really sometimes bothers me.  My son is 13 and I think he knows if he is feeling ill, not once have I ever had to give him an injection, and he had been sick with the flu pretty bad a few times.  Just upped his dose, and he always does fine.  He went through the weight gain, I took him to a dietician it got so bad, he is thinning out somewhat now, but he’s still heavier then I think he normally would be without the meds. His height is fine, he is around 5’6.  I had read somewhere that some people, even though their levels may be high, they are able to deal with it.  Just wondering how it was your son came to be diagnosed?