Buying an eye wear without PD (Pupillary Distance) would worsen your eye vision problem. Nowadays, you can buy Corrected lens eye wear with PD online. All you have to do is ask your optometrist for your PD prescription after the eye examination. Many think that the only place they can purchase their eye wear is in the clinic of the person who examine their eye vision problem. They do not know that PD empowers everyone to purchase eyeglasses from any supplier even online.
My colleague learn her lesson the hard way from buying an eye wear from a sidewalk vendor. Her eye problem would not have been resolve if she did not listen to my advise to throw away her eye wear without prescription. Better to buy your eye wear online as long as the eye wear follows the PD number prescribe by an Optometrist than from a sidewalk vendor that don't have any knowledge about PD number at all.
Sidewalk Vendor's eye wear cost you less but would would not resolve your dizziness and poor vision problems.