Paul, the brake pedal returns up to the brake light switch when you release it so all you need to do is adjust the brake light switch with a pair of long nosed pliers then release the pedal carefully and it will reset itself.
Just pull out the black centre plunger which you can do in situ.
Somewhere along the line you have pushed up the brake pedal beyond normal and reset the brake switch too high. Easily done as you just need to trap your foot under the brake just the once and you've reset the switch too high
Mitchellinman, what fun symptoms! I think you have a different problem. As your headlights suddenly stopped working ( be a bit bizarrre if both bulbs went at the same time) then i'd be looking for light switch/ light switch connector problems or bad earths. I'd check out the indicator/ light switch connector at the steering column as the light switch is turning on the brake lights by the sound of it.
You didn't make clear what happens with no lights on and brake pedal on/ off
Also, are your tailights going on properly when you select sidelights or headlights? If not then you might have a bad earth at the rear of the car
It's kind of weird but the way the brake lights work is that the lower brake lights are fed directly from the brake light switch but the upper brake light is switched on by the body computer when told to do so by the brake light switch. That's why you can get lower brake lights off and upper brake lights on/ off combinations