I've had conjucntivitus for a week now and my doc said that it should be gone in a couple of days last week. It's in both of my eyes and is quite sore as it feels like it drying them out. Is there any way to clear up conjuntivitus quickly? Could it also be because of a vitamin or mineral deficiency that I haven't thown it off yet?

Have you returned to your dr?
Conjunctivitis is extreamly contagious you only have to not wash your hands once from touching the eye area and it will reinfect the eye.
You have to be extreamly careful when washing your face and don't use the same face cloth twice same with your towel if you use it to dry your face then your just passing the infection back.
If you touch your eyes wash your hands afterwards.
You need to go back and see your dr eyes aren't something to mess with you only get one pair after all.

Can conjunctivitus effect your eyesight?

If left untreated I would imagine it would yes

If left untreated it will damage the conjunctiva of the eye. I am not sure about the eyesite, but it sounds possible.

It does sound as though you have reinfected yourself, and a trip back to the doctor is in order.