PLEASE HELP ME!!!

My hair naturally very dark brown (almost black) over the summer and around Christmas time I got it cut and dyed with a lot of blonde in it - mostly on the top like.  So in November I broke my ankle badly and was out of work and couldn't afford to keep up with it, but my hair grows super fast and finally about 2 weeks ago I was sick of it half brown (the roots) and half blonde I tried to dye it black.  It was okay for a few days, but now where the blonde was it's grey looking.  I couldnt notice it, but a few people pointed it out to me.  So on Tuesday I put some more black dye in hopes of covering it up and it isnt helping.  What should i do?

I have 2 boxes f burgandy dye laying around that I was going to try...I dont even care if my hair is two different  shades of burgandy, I just want the grey gone.  I am only 24 years old and it makes me look like I have gray hair.  Haha.  And I just started a new job in a financial office, so I want my hair to look decent. 

Can anyone help me?  Will the burgandy help at all?

Thanks so much!

Just sounds like the black color is just washing out...I dyed my whole bleached blonde head black and never had a problem, it went more brown than black after-a-while but that's it. You should use a protien filler