I experience occasional peripheral vision shadow on widening my eyes. What is it?

Hello doctor,

I am a 19-year-old male. I have been to a few ophthalmologists about this and they seem to think it is benign. But I want to get some other input on this. If I widen my eyes and move my head around, I can see shadows in my far peripheral vision moving as my head does. And it seems that the shadows change and become different sizes as time goes on. Now I do have astigmatism in my right eye and from time to time I get aching, almost gnawing pains that are with the movement of the eye. And has happened in both at the same time before. I find that it happens mostly when I am in a place with very weird or bright lighting or when I am looking at a bright screen in a weirdly lit room. I suffer from anxiety and depression which is why I guess I am coming out to ask some more questions. And I also have Asperger’s syndrome. The aches radiate to my temple as well. But as I have said I have been to doctors and they have dilated my pupils and looked at my retina and ocular nerves and told me they looked good. So I honestly do not know what could be causing these weird shadows. I have had them for quite a while. And they also get bigger and more noticeable with head tilt like when I exercise or go running or do something very physical. I currently take Prozac 20 mg and Pantoprazole 10 mg.