I have a little purple dot on the top of my right eye that ends at one of the veins and i don't have it on my left eye. it hurts every now and then?

Axenfeld nerve loop: You seem to be describing a normal anatomical discovery of an anastomosis of the long posterior ciliary nerve that pierces the sclera and turns to travel to the ciliary body. It often has a slight pigmentation around at this point, especially in dark pigmented races. Manipulating this area sometimes elicits pain. It is otherwise a benign normal structure.