I have naturally brown hair. Last week I dyed my hair permanently using a shade called natural dark brown. The result was more like unnatural goth black. I hate it but it is permanent. Is there anything I can do to fix this that doesn't cost an absolute fortune or wreck my hair?

Honestly? I have the same problem and I have thin hair. I know you want to save a fortune, but you know, it'll be less damaging getting it done by someone who knows what they are doing. The cost of repairing the damage will be emotional and monetary if it goes wrong with a home repair kit. My hairdresser said the only way to get the black out of my hair is either grow it out (I'm not patient enough) or strip it (I'm considering it). I have to keep conditioning my hair with conditioning treatments 3 times a week till the day I sort the colour out and kep conditioning after.

Remember that hair color will gradually fade every time you shampoo your hair. You can try to fade the color by using Prell, dandruff shampoos, clarifying shampoos or dish detergent. If you want to color your hair from black to brown without the red/orange shade, you will need to pre-lighten your hair and then apply your desired color. You should consider going to a salon. They may be able to achieve your desired color, minus the brassy shade.