When new brakes are installed and used for the first few times they give off a distinctive odour. Also, anytime the brakes are worked hard (say coming down a mountain) they will give off the same smell. That is perfectly normal. Hopefully what you experienced is not anything more than that.Third, there is a slight burnt smell coming from the brakes after a drive, which cant be good, lol. I think its because the rotors and pads were just installed, and it was just the brake-parts-cleaner thats being burnt off, but i dont know...
Hot brakes should smell like hot brakes. If you do smell something more like a burnt smell, you should have it checked out.