Hair-dying horror! well, not quite horror, but pretty bad :/

ok so heres the story.
i had a succession of bad haircuts at my local salon (which, safe to say, is no longer `my` local salon) and in the end decided to get something done about it.
So, i cut my hair short and spiky and tried to dye it red, which for some reason came out bright orange.
Not quite the colour I wanted but cool nonetheless so I kept it.
Im now growing my hair out and am futilely trying to dye it back to black but for some strange reason none of the dyes will stick.
Every permanent dye I use for some reason fades out after a week or so of washing (not washing every day, so that would make it, like, maybe 3/4 washes) and the lower part of my hair which was orange turns a weird blonde then back to orange again and im back where i started.
Long, two-tone hair; black roots evil orange coloured ends.
Does anybody out there have any reason why this keeps happening, or know of any treatment/dye which will work, pleeease.
I`ve vowed never to cut my hair again but I might have to if I cant get the colour sorted :(
Help!