Your brake switch maybe bad or the bush on the pedal side has fallen off, preventing the switch from engaging. If you look under the dash and follow the arm of the brake pedal all the way in, you should notice a plastic box with a connector going in. You can twist it and remove it. Once you do this, depress the rod in the box inward, your lights should switch off, if the lights switch off, you are good and you would need to inspect/replace the bush that hits the switch. If it doesn't switch off, you would need to replace the switch.
Hope I didn't confuse you.