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JCH MD
Based on my experience, you are having tired eye and now it is getting dry.
Try to wash your eye, if the spot still there, you should meet your eye doctor (probably cataract).
If it is not permanent, then:
Dont work too much, take a long break, 5 days vacation.
Read also how to relief from tired eye and dry eye.
My suggestion dont put any chemical on your eye before you know what happens.
cheers