If i have an early glaucoma, does this affect my vision by time?

Not necessarily: Glaucoma is damage to the optic nerve, usually in relation to increased eye pressure. Early diagnosis can allow the disease to be controlled, usually with pressure-lowering eye drops, preserving the vision. In severe cases, surgery is sometimes required to control the pressure. You should be followed by an ophthalmologist to monitor for glaucoma progression.

Possibly: Glaucoma can be vision threatening if poorly treated or undetected. The goal of therapy is to get the internal pressure into a safe range so that the vision is not affected. In most cases the vision will be preserved. It is a bit of a difficult motivation task as the use of eyedrops for glaucoma does not produce an immediate benefit (like a pain reliever would) so treatment is for the long term.