twice in one week?

Using color to fix color is not a good idea...especially when going lighter.  Longhairdreams is right.  Give it a few washings; use some clarifying shampoo.  It will lighten a bit on it's own.  The odds are that using the permanent color over what you have will leave you with black hair or something funky (and I mean bad funky). 

What is your natural color?  That will partly determine what the color fades to.

I colored my hair Monday with a med.ash brown semi-permanent. Came out a very dark brown almost black. 
Now I want ot color it  again using either Feria hi-lift browns or True brunettes.  Is this a bad idea? I so want  to have brown hair.
thanks