That's another problem with the on line exam. My doctor has a running record for the last 15 years. During that time, I have only gone to her 3 times for an exam.
If your eyes rapidly change, it's even more of a reason to have a doctor take a look.
Your "logic" doesn't hold up.
Bet there's a great big liability clause to the on line stuff....that's too small to read. ;-)