[GAMEPLAY] Black Particles on screen

You can see here that on the top side of the picture there are black spots in game. They were very minimal however they were at the top side of the screen throughout the whole game. As I moved the map the black particles moved and changed in size. I've never had this problem before so I thought i'd post it here. I asked everyone in game if they had it and they did not. Happened at the very start. Got into a second match and it didn't occur. (account is my smurf) EDIT: It happened in the next match I got into.