Could you describe in detail what problems do you have in focussing?
Do you sit on computers a lot?
Has dilated eye examination been done?
I am not sure but you may be having an anxiety disorder. I believe most of the possibilities for your symtoms have already been ruled out. Anxiety can also cause these symptoms. You should discuss this issue with your general practitioner and if he thinks it to be necessary get a referral to a psychiatrist/psychologist for evaluation. If it's due to anxiety then anti-anxiety medications may be very helpful. I hope, you understand. Thanks and best wishes.
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