What Causes Floaters In Vision Followed By Nausea And Dizziness?

I had vertigo 2xs years ago with everything going in circles. I have not had it for years. Lately I had systems of: what I was looking at would move left to right across my vision sight, it would go 2 to 3 times. I would last only seconds, then it lasted maybe 1 min. Then I would get nauseated and feel bad for some time, sometimes all day. Now I seen to have dizziness for very short times, sometimes when I move my head, sometimes just when I am still. It seems like my brain moves with the dizziness. Now I feel like I am right at the point of dizziness most of the time. I do have a maengeoma(sp?) in the left lower area of my brain. Do these symptoms sound more like inner ear or maybe the tumor?