Wrong hair color. what can i do? need couple of shades lighter.?

Today I darkened my hair. it was supposed to be just a few shades darker but it came out REALLY dark. I dont like it, i wanted it just a bit more darker, not like this. I tried washing it with soda and lemon juice, head and shoulders shampoo but it didnt work. Its a semi-permanent color. Its supposed to last for 6-8 weeks, but i know that even after that my hair wouldnt be the color it previously was. I would like to lighten my hair just a few shades. Is there any way to do it without bleaching? Some kind of shampoo maybe? My hair is naturally light brown, i used to color it lighter before this time.