Blonde dye fade-- HELP!!!!!!?

So I'm a brunette who 2 1/2 months ago dyed her hair blonde and I've been using john frieda's go blonder products to keep it that way. Only now I want my brown back, but my hair is a weird shade of brown and other dyes are either too light or too dark and I dont want to have to deal with roots showing and such again.I've been letting it fade natrually-- only it isnt. My roots just look terrible, but no other fading. So i've used dish soap, but no luck. And now I have a really important buisness party coming up and I dont want my hair looking like this! HELP!!!!!