Yesterday, I Suddenly Saw Black Swirling Circles, Lines And Dots

Yesterday, I suddenly saw black swirling circles, lines and dots - like blowing grains of sand formations. Mostly in the left field of vision in my left eye - quite scary and it lasted most of the day and night with varying degrees of intensity. Have had all day today to a lesser degree, but am concerned because it's compromising my ability to see normally from my left eye.