Pain

I recently at work, swung my left hand and hit quite hard, on the knuckle of my little finger and the next finger along, into a door way when walking thru. I iced it straight away, and kept ice on it for as long as i could while also trying to work. There was not much bruising at all, but now at the end of the week it is still sore and there is a very faint purple/blueish line running down through my knuckle and half way down my little finger. It hurts to bend it and some movements really hurt. I am just wanting to know if it a bruised nerve and will i need to see a doctor?