I have a tender/painful lump on my right labia majora i noticed while showering that wasn't there previously?

Bartholin gland: It could be an inflammation of the Bartholin gland. If you are sexually active, then it is more likely. If the lesion does not subside in a day or so, it would be prudent to see your doctor. If you get fever, purulent discharge or bleeding from the lesion, you may wish to go to a hospital emergency room for treatment. For good health - Have a diet rich in fresh vegetables, fruits, whole grains, milk and milk products, nuts, beans, legumes, lentils and small amounts of lean meats. Avoid saturated fats. Drink enough water daily, so that your urine is mostly colorless. Exercise at least 150 minutes/week and increase the intensity of exercise gradually. Do not use tobacco, alcohol, weed or street drugs in any form. Practice safe sex. Get HPV vaccine.