Have an evaluation with a retina specialist for a complete dilated exam. I would also have a visual field performed.
I was in a simlair position as you, before you visit the retina doctor, I would request for an Electroretinography (ERG) which is an eye test used to detect abnormal function of the retina (the light-detecting portion of the eye).
The retina doctor will mostly likely request this test to performed first, physical
Exams showed no damage for me either, normal erg found the problem , which lead to the advance version of the erg and Goldman visual test