Your item looks like quartz, but I do not see any alterations by man. I appears to be a natural rock that has eroded with time.
It may be helpful if you study and read about the Indian artifacts that are found in your area. Also study how the projectile points were flaked. Once you understand how they were flaked you will instantly know that you have found a real artifact. If you find something that you are not sure of post, a photo and I am sure that someone here will help you. Just keep on hunting and sooner or later your bound to find a real keeper. Good Luck!