You all are not going to believe this, but it turns out that it's not a chip or crack. It was stray silicone. As it turns out, it's pretty hard to tell the difference between surface silicone and a chip in the glass with your finger. I talked to the guy and he said if it was a chip, it would be clear. If it was a crack, it probably would travel in a relatively straight line. He was nice about it, and he made good points. I didn't want to believe I could be that stupid, but I got home and scrapped it off with a razor blade.
Crisis averted. Carry on. Thanks for all the concern!