Could blindness occur after fillers?

Yesterday I got some fillers done for rolling scar on cheeks and chin. They were Restylane Silk and Juvederm Ultra plus. I when to a hospital were resident are the one injecting with his superior guiding them. I was not told of side effects. When I came home I started researching the fillers. In some rare cases it could led to blindness.I have two small bruises on my chin. If blindness was about to occur would it been right there when I was injected? Or would it take days to occur? Please help