Ok this happened to me like maybe 4 times in my life...I was in gymnastics when I was younger and sometimes when I did back walkovers and cartwheels I would see dots...But the other night I was at my cousin's house sitting down on the couch and I was talking and I started to laugh and kinda moved my head down a tad bit, and all of a sudden I got this feeling like a light-headedness feeling like tingling in my brain and I saw black silver dots like moving really fast up top, like if i tried to look at them they would scatter..they weren't floaters though..they were silver black dots that I could see through my peripheal vision above my eyes ..they weren't infront of my face but above..I have no idea what this could be. It happened for like 10 seconds and then went away..Then after if I just sat there and kind of put my head down like I was looking at the floor..I felt very dizzy like a swaying kinda dizzy..like back and forth from the left to right..I don't know what it is.