Depending on the memory card, these things can record several hours of video, definitely more than your flight will last.
If you get a 200-plus pound camera, don't skimp on a 20-pound memory card. Get the largest the GoPro supports (32 GB) and make sure it's fast enough (class 4 or better).
A 32 GB card is sufficient for about five hours of HD (1920x1080) footage, while the GoPro battery will last for about 2.5 hours. (If you get the GoPro battery backpack you can actually use two batteries simultaneously, which brings the endurance to about five hours as well.)
Yes, that is well beyond the duration of a typical first solo flight. But you might also want to use this to record your QXC, and that might take three hours total.