I guess I jumped the gun - I took my ring in today and it seems that a small shard of metal from the ''squashed'' prong was making it look and feel like a chip. PHEW!!!!!! My diamond is OK!!
My girlfriend thought that her ring was chipped too. After a lengthy inspection with a loupe, I found out that it was just a reflection of some dirt stuck near the prong. It's gone now. I had to scrape it off with a toothpick.