Very weird that both lights are on. Should be 100% independant of each other.
Maybe try to check the resistance across each sensor by disconnecting them inside the engine bay.
They should all be the same.
Failing that check that the sensor wires are still ok. Should be fine because they are pretty heavy duty.
Also check that there is no build up on the sensor face. They are magnetic so little bits of metal will stick to it which can screw it up.
The hand brake light coming on intermittantly would make sense if your fluid was borderline low.
If it's on the high marker it should be fine though.