3 days ago I bought a demi permanent highlighting kit in red for my hair. When I used it it leaked and turned my hair pink instead of red. I have washed it at least half a dozen times since dying and it has faded to light pink. My hair was bleached about a month and a half ago. I am really worried that this dye will not wash out and will stain. Should I persist in washing it or bleach over it? Is there any shampoo that will get rid of it more quick?

I did that same thing, and mine turned out pink too. I washed and washed and it wouldn't come out. I ended up having to go to the salon and have my hair dyed professionally, to dark brown. Luckily, I loved the dark brown, otherwised I would have been mad.

That might be what you have to do, just re-dye your hair all one color. :)

Demi permanent color is stronger than a semi-permanent color. It's a deposit only color that will make your hair darker. If your original hair color was red or light, demi-permanant color may not wash out. Both semi- and demi-permanent colors can become permanent on permed or already-colored hair. You should consider going to a salon and have them strip or lighten your hair. Remember that when they strip the color, it will leave your hair in a brassy state, and it will need to be re-colored in order for it to look natural.

I don't think I can afford to go to the salon because it will be very expensive. Would putting pre-lightener over the top of it work to turn it back to bleached blonde colour?

You can pre-lighten your hair with bleach (hydrogen peroxide) to yellow stage and then apply a neutral blonde toner if you want go back to a blonde color. If you can't afford to go to the salon, ask someone that has experience in hair coloring to help you do the color applications.

I read on the loreal site that you can mix shampoo (not for color treated hair) with 20v peroxide and baking soda, wash your hair with that mixture then DEEP Condition. It is supposed to fade the demi and semi color from your hair.