Schwarzkopf live xxl real red!

So i really wanted to get my hair dyed and couldn't afford to spend £100 at the salon so i bought 4 boxes of schwarzkopf live xxl real red only needed to use two and got two for whenever it fades.. anyway, i dyed my hair and washed it out, once my hair was dry i looked it at in the mirror and my roots have gone a really nice bright red until about 2/3 inches down it gets a very dark red :S would applying another box of dye to the dark red make it brighter, darker or would it just stay the same? dont want to add more to it and damage my hair more if it will just stay the same or go darker! x

Edited by JLF0x - February 24 2012 at 8:33pm