To know if you are overworked, you need to measure both visible and invisible tension. The sum of both is your total tension. When this total tension lasts too long, you are overworked and your nervous system becomes overexcitable. You usually notice this by the irritability of your feelings and reactions. To accurately test how high your tension level is and whether you are overworked, it is best to take a good online self-test every other month so you can follow your evolution.