Hi dear , This is very common problem . There are many factory that can trigger the occurrence of pimple and dark complexion.like sun exposure , hormonal changes and stress . I would suggest you to wash your face with facewsh containing benzoyl peroxide and cold water daily twice a day , apply cream containing azelaic acid after washing face , exfoliate your skin twice a week and apply vitamin E oil at night . If condition doesn t improve in a month then consult dermatologist for proper examination . Doctor may prescribe retinoids , steroid ointment and antibiotics like minocyclin. Hope your concern has been resolved. Get Well Soon. Best Wishes, Dr. Harry Maheshwari