How short a time can I leave it between home hair dye sessions?

[Hassled]

I dyed my hair this morning - some herbal but permanent stuff I bought from the local healthfood shop. It's a complete disaster - it's meant to be Chestnut Brown but looks more purple - I look like I should be at a folk festival with a dog on a bit of string . Or slightly goth - I can't decide. Whatever - I'm just too darn old for hair this colour.
So - can I just go and buy a pack of Clairol type stuff today and restore order, or will that make my hair turn green and fall out?

Bump - anyone?

Hassled, I did this a few years ago, bought a colour and it came out completely awful, paper bag over head job! I sent my then dh out to Boots to get another colour and just went for it. Hair was fine, I just gave it loads of extra conditioning treatments for a while after.

Probably some might say don't do it, but if you can't bear the colour that's hard to live with isn't it.

Hope you get it sorted

Phew! Thanks - I'll give it a day and then redo it. I do feel like never leaving the house at the moment - it HAS to go.

test a bit of herbally dyed hair first tonight and do it tomorrow, just to be on safe side