Is there a possibility that i will past my drug test

I guess there's a possibility that they find residues in your hair after three months, but it seems to me highly unlikely if you haven't been using for a month as you say. If you wash your hair regularly, after a month I think you could be clean.

I never used myself, I can't tell you for a fact.

Good luck, man 

alright from my understanding is that drugs stay in your hair forever untill you cut that portion off. its kind of like a candy necklace, the elastic part is your hair and the candy is the different types of drugs that you have used. but if they take a full strand of hair, and say you havent done coke in a month than the portion closest to your scalp will be clean but a months worth of growth up on your hair you will have evidance that you have done cocaine