I dyed my hair turquoise now its green?

Yikes, that is a lot of colour. I wouldn't try to fix it up yourself this time. It is really hard to dye black hair. When ever my asian friends try to do it, it turns out horribly wrong and they end up going through the same process as you (so I have sympathy - It is not fun!). My cousin was in the same position as you a while back (she tried to fix it so many times and eventually went to a hair stylist who told her that if she had have tried to fix it herself a few more times, she would have had to chop all of her hair off). So my advice to you, would be to go to a stylist to get it fixed this time. Don't risk it right now to dye it back or to fix it. I know that it is expensive..I dye my hair red every few months. But for the fix I would do to a stylist and once your hair has a break from all of the product ect, you can try to find out with practice what works for you. It will be tough because you have dark hair, but pretty soon you will be able to figure out what works and what doesn't. Good luck.