I was walking down the high street when I started seeing flashes, then tiny black flies floating around my head that had me waving them away. I went straight to the optician, only about 100 yards away. He saw me straight away and after using some high-tech looking gear told me that my retina was detaching! Had I had any knocks to the head recently (err, yes!). He also told me that the black flies were bits of retina floating about in the eyeball casting shadows on the retina. They are called "floaters". He told me that my brain would soon start ignoring the floaters. It did, but for a while it was though I was afflicted with a plague of money spiders. People thought I'd gone mad, waving away unseen insects.
Having established the scale of the problem as minor, he booked me in for a more thorough examination a few days later. All was confirmed. I needed no treatment and everything he told me came to pass.
I don't like the idea of an eye operation, but if people can have cataract surgery while still awake (my mate) and have injections into their eyeballs while awake (my mother), then how bad can it really be?
Best wishes!