My Doctor Prescribed my Epiquin Micro (Hydroquinone 4%) to Reduce the Black and Brown Spot

I am using it daily twice and its been a 1 week almost, i am noticing the color of my face is getting even, but however the overall skin color is becoming dark. Now my face is darker than my forearm, is this normal and will my face became lighter after i stop using hydroquinone? or should i notify my doctor and use some other topical cream?