High intraocular pressure can make the retinal nerve be oppressed, which then slowly lead to vision loss, this is glaucoma. Having a good rest can make the intraocular return to normal, unfortunately, this is not likely. So if you do not have a treatment, your eyes will in a state of high intraocular pressure, and it will gradually become worse until blind. Id it is not acute glaucoma, this process may be very slow, perhaps it will takes a few years to go to blind. In any case, you should have a treatment early.
I can't tell you how long does glaucoma take to go blind without treatment because without mote information about your age, your history and the severity of your glaucoma. In fact, it mainly depends on the severity of your glaucoma. If you have severe glaucoma, it may go blind quickly. If your glaucoma is mild, it will takes a number of years. According to your description, you may just have mild glaucoma since you had glaucoma for a few years.
When the high eye pressure is untreated, it will result in glaucoma eventually. People with glaucoma should go to see a doctor to have them treated as soon as possible. If it is untreated, glaucoma will result in blindness gradually. However, how long the glaucoma will take to go blind depending on the condition of your glaucoma. If it is serious enough, it may cause blindbness very quickly like weeks to months. If it is in the early time, it may take years to go blind.