Things will generally change quite quickly once diagnosed and treatment/monitoring commenced, so try not to worry too much. After only a month a lot of the second reading will include most of the first (if you see what I mean!).
From what I have read I think children find it more difficult to get into the 6s because of all the growing, hormones, shifting activity patterns, childhood illnesses etc. so don't stress too much on getting below 7 (I'll probably get corrected by loads of parents now for saying that! )