You probably did not scratch it, since it is glass.
A plastic lens is another story.
Here is what Kodak says about cleaning a lens:
If the lens appears dirty, breathe on it to form a mist and wipe the surface gently with a soft, lint-free cloth or a camera lens-cleaning tissue.
Never wipe a dry lens.
Do not use solvents or solutions not designed for cleaning camera lenses.
Do not use chemically treated tissues intended for cleaning eyeglasses.
When I took my new DX7630 out of the box, I accidentally touched the lens with the plastic wrap around the camera. I tried cleaning it with a Kleenex, but that only added more dust.
Since I used Kleenex to clean it, was the lens scratched? Is there anything that removes scratches and dust in a way that doesn't degrade image quality?