I messed my hightlights up... what is this symbol?

[Dan12]

 

I saw this symbols floating over the text and clicked it and now there are flowers and blue boxes all over the book.. how can I delet it... and what are this 5 floating symbols?

 

(I put in the symbols like the lamb or the crown and the "you" blue box intentional!)

[Lorinda H. M. Hoover]

The section you circled is allows you to quickly pick some of the most recent highlighting styles you have chosen, or to undo highlighting in the section you have selected (the eraser).  The paint palette opens the full "palette" of highlighting styles.