I dyed my hair dark brown about 2 months ago. I had light brown hair and I Wanted to darken it up. Well now, I'm trying to go light blonde and it's not working. My roots are pretty darn blonde (yellowish) but the rest of my hair is MAYBE a shade lighter. Please.. how do I fix this? I need to give my scalp a break today b/c it felt like it was on fire. I forgot the brand I got doesn't agree with my scalp. Every other brand is good but this one made me feel like my scalp was on fire.
Any suggestions?

If you want go from dark to light blonde, you will need to lighten your with bleach (hydrogen peroxide for hair) to a yellow stage and then apply a blonde toner. If you want a decent blonde color without the unpleasant tones, I recommend that you get your hair professionally done.