blonde to brown gone wrong

Ohkay so i was platinum blonde, veeery white, anyways i wanted to be dark again for winter, so i did the right thing and went to get it done by a professional. So they put the brown straight on, no filler nothing, i was soo shocked i couldve cried, and so i questioned the stylist about how it would turn green and she told me the brown she chose had red in it, and that it would be enough & if we needed it that she'd reapply the brown again. But she went with just the first application and attempted to dry my hair (or what was left of it because there was ALOT of breakage) and i think she could see it going green so she told me she didnt want to continue drying because my hair was in such a fragile state. and she let me leave with a terrible shade of brown wet hair. Next day i washed my hair and it all pretty much cum out, my hair is soo patchy and khaki its terrible, i rang my hairdresser she told me to get a semi from the supermarket and that id have to colour my hair a couple of times a week for it to grab. its been 3 weeks and nothing has changed. its terrible i dont know wat to do.. ive tried other hairdressers but they just say the same thing, theres nothing they can do & to keep trying at home semis hopeing that it eventually grabs. And to pretty much wait for it to grow out. surely there is something i can do??