How long does it take for Accutane to work, will I get my beautiful dark complexion back? (photo)

Hello Doctor , I have been on acnetane 20mg for 40 days now ,I have seen no improvement ,actually im getting worse, I avoid taking pictures more than before. My complexion has become darker and I look very ill as the medication is making the acne worse and painful. When does this stop,sometimes I actually regret even taking acnetane. My doctor keep saying it will work but I'm loosing patience.