OK well I took peoples advice and didn't dye my hair red for quite a bit, I just use stargazer eggplant semi permanent which makes my hair slightly pink were my blondes coming through but it washes out in like three washes, any way when I wash it my hair has become a slight light brown colour, what can people recommend to lighten it, I want to go back to my original dirty blonde but I don't mind going a darker blonde, is there any stuff I can buy to lighten it.

Another girl was having issues about going lighter on colors and what I did was use laundry detergant (tide) when I washed my hair... it pulls the dye out

They have something called sun-in. You put it in and it gradually lightens your hair. Be careful though, It might make you go lighter than you intended. Just look at the back of the box. Good luck.

I've tried sun in and it turned my hair gold