Hi Gini,
to the site.
I really hope that your son is not Thal. Major. However you should keep an eye on his health. Make sure that he is developing nicely and his blood counts are monitored regularly.
I suppose that the HB switch has occurred to him; i.e he is now on his own HB rather than his mom's Fetal HB so a Electrophoresis could be helpful otherwise his reading would show high HBF readings which could be misleading for now.
You should keep a close eye on his blood counts as some Thal. Majors are known to pull through the first year without a Tx (I pulled through some 2 years or so).
Make sure he is active and has no delayed milestones. If he gets sick frequently then have his blood counts checked.
You need not worry if his HB stays around 10 g/dl because the doctors will consider it low as it is a low for a normal person, however it is pretty much normal for a Thal. Minor.
Finally if a DNA test is available to you, then you can get the exact picture of what genes he has.
Wishing you all the best.