I slipped and fell and hit my head and I was getting really bad head spins, dizzy spells, after they quit now I am seeing flashes of light on the corner of my eyes?

Possible damage to nerves or optical imput.

What did the hospital and ER say about your injury.
If that answer is "i did not go" then go.

Years ago I had a car accident that put my head through the windshield of the car. About a week after getting out of the hospital, I started having a flashing light now and then in the corner of my eye. I went to get it checked and they couldn't find anything with it right away. About 3 days later I had a seizure...a pretty bad one. Well, the light was gone but that sure wasn't the way I wanted to get rid of it.

Not saying this will happen to you but for sure you want to go get it checked out.

It is called a 'concussion' which has varying degrees and all need medical attention immediately.