first dr appointment

So this one is a little out of order. Archimedes had his first appointment on May 11th. He was 10 days old. He weighed 8 lbs 6 oz and was 21 inches long. He was 7 lbs 13 oz when we left the hospital (7 15 when he was born) and they said he was 19 3/4 inches long at the hospital - although I think that the length measurement is a hard one to get accurate..) either way, he's gaining weight like crazy! Hes in 0-3 month close now instead of new born for the most part.. but he's still wearing new born diapers. I dont really want him to grow very fast.. I really want him to stay little for a long time!