I was driving a friends car on highway in a 2010 Mercedes for 9 miles @ 60 mph with the emergency brake on, the rear tires smell like burnt rubber. Do I need new brake pads???
About the same thing happened to a woman I know. She went down the road in a Volvo with the brakes smoking like crazy. Eventually some nice man got her attention and she discovered her error. Prior to that the car was just not as "peppy."
The shoes (rears were shoes for parking brake, and disc pads for main brake) were ok, but the paint I used on the drums was burnt off.
I married her anyway.
Maybe, maybe not. What is certain is you should have them properly inspected as soon as possible, then you will be confident you have a good set of brakes whatever the outcome.
I saw a car that did this V6 Capri on a road test for 20 mins - new pads and discs on back, when it came back into the workshop the discs were red...