How long does it take to get used to glasses?

I'm farsighted and just recently got corrective lenses for it. At first, I couldn't wear them all the time like I was supposed to because it gave me a headache and made my eyes hurts; also, while I could see perfectly out of my left eye, my right eye was reduced to nearsightedness. After a while, my right eye has gotten much better, but it still isn't like the left eye (each eye has a different prescription). How long will it take before my right eye is seeing as well as it should?