2 weeks is far too soon for a permanent hair dye to wash out.
I bought this in Starry Night, a neutral black, and for the first couple of days, it actually was a nice black (as long as I stayed out of natural light, because then it would be a very bright navy instead). Then, little by little, the colour washed out. Within two weeks, my hair was a strange mix of dark brown, medium brown, red brown (from the red layer I had beforehand), and a few black streaks. I absolutely would not recommend this at all. Two weeks is far too soon for a permanent hair dye to start to fade, I think, but it might just be my hair. I don't know. This has honestly never happened to me. (By the way, it's been a month since I used this, and have yet to redye my hair with a new colour - it's currently a mismash of dark browns and red browns with maybe a single black streak left. I thought black was supposed to be one of the most permanent colours in hair dye?)
