Mis Shifted Grinding Sound Stick Shift

My wife was driving our new SUV back from the dealer with less than 25 miles on it yesterday and it was at night. She had gotten confused about the shift pattern and instead of going into 5th gear she moved the gearshift lever down almost as if she was going to go into reverse when she heard metal on metal and immediately corrected what she was doing and put the lever up into fifth. I am freaking out thinking that she ground gears or something. The car runs fine, no problems but I am wondering what the metal on metal sound was. Should I assume that I have metal fragments inside of my transmission now or was that just the pressure plate or what? If anyone can help I would certainly appreciate it. This is a brand new car!! I know in the past when I have had sticks I at times rarely when I didn't have the clutch down far enough did something like this but she was on the freeway, not that it should matter but I don't know.