Why Has my Face Gotten So Dark?

I'm an African American woman beginning my 3rd month of Accutane. Over the course of the treatment my face has gotten very dull and grayish and is several shades darker than the rest of my body. Is this a normal occurrence? If not, what measures can I take either during or after treatment to even my skin tone? Also, I have a lot of scarring (ice pick, boxcar, rolling and hyperpigmentation). I have heard that Accutane may decrease the severity of it. Is that true?