My son is 8 years old and has been having abnormal blood work for 2 years now?

My son is 8 years old and has been having abnormal blood work for 2 years now and I’m not sure what to ask the doctors to look into. Unfortunately if I am not a bit forward we don’t even get a call back about his blood work.

Vitamin D 12/29/16 24 ng/mL
MCHC 12/29/16 33.3 g/dL 7/27/16 34.2 g/dL 3/10/14 33.2
HGB 12/29/16 13.0 g/dL 7/27/16 17.1 g/dL 3/10/14 13.5
RBC 12/29/16 4.43 7/27/16 4.44 3/10/14 4.73

He has many headaches, fatigue, is not very active. I brought him to a pediatric neurologist with our native clinic who only asked questions and did no tests. It seems if I am not specific on what tests to run I really get nothing. I have asked for vitamin D for him to get the levels up. We live in Alaska, but at sea level and no one smokes. I’m concerned about the HGB levels and can’t think of any reason for them to be up to speak with a doctor about.