It could be a utilized flake but it also could be only debitage which I think latter is more likely.
https://www.google.com/search?q=bul...UG01kKHcQkCbYQ_AUoAXoECB4QAw&biw=1920&bih=937
Both sides show what appears to be use wear scars at several points along their edges if you look at them closely -- which is what you do when you're trying to determine whether a flake was used. If it wasn't used, and used forcefully enough to remove chips, these flake scars remain to be explained. Illusions ?
FWIW