I dyed my brown hair, (medium dark with grey) with the xxl live colour, hair dye last night, a vibrant red colour, it has really worked on the grey bits and the bits were i dragged the dye through it, and over all my hair is redder, however my hair is thick and long, and i thought 2 boxes would be enough, i want to put another 2 boxes on to try and get it really red, does any one know if i can put the next boxes on tonight? All my work colleagues are saying to do it, but its not their hair!! Just don't want my hair to fall out, any advice would be fab.
No, don't do it. It will over-process your hair and it will end up dry - or at worst, break off.
You need to give it a rest now with the permanent dyes - if you want all over colour look for a vegetable dye like La Riche Directions, this won't damage your hair. It may not take as well on any hair that you have missed with the permanent dye, but it should even it out and hopefully make it redder.