My vet told me that the only way to tell if the glands are too full is by internal exam, expressing the glands -- which, in my non-expert opinion, is a risky proposition. The glands can be impacted and ruptured if done wrong.
Impacted glands ultimately ulcerate to the outside, around the anus. Does Mya have any red spots or irritation around her anus?
My Max's breeder suggested that instead of expressing glands manually, feed green peas or green beans to give more bulk to the stools. Larger stools will express the glands naturally.
Usually dogs will scoot if the glands are the problem (or maybe Max did this because he can't reach to lick.
) There are other causes for licking, like general irritation from a little stuff being left behind.
Hope Mya is okay!