Well, yes, it is possible to have glaucoma in one eye. And generally speaking, glaucoma is a kind of dangerous eye disease which, can lead to blindness. And when it occurs, some symptoms in the eyes will happen. For example, you may suffer eye pain, vomiting, even vision problems. But on the other hand, when the disease progresses, damage to the optic nerve grows worse. Finally, side vision can gradually fail until there's only tunnel vision left. What is more, blindness can occur. So it can be dangerous to have it, and you need to pay more attention to it. For your situation, you can just try some green tea. And nowadays, some evidences have shown that green tea contains catechins which can reduce harmful oxidative stress in the eyes that is linked to glaucoma and other eye diseases. Anyway, you can just drink them to treat your situation.