Ditto, ditto - get to a good doctor.

An optometrist commented to a friend of mine that she had had histoplasmosis. (which many of us in this area have been exposed to) Later she started losing vision due to a rare side effect from that disease which affects the retina. She was angry that the optometrist didn't elaborate - but it wasn't his expertise.

Many diseases can affect the optic nerve - swelling, paleness, etc. Get to a good doctor.