I color my own hair at home with clairol natural instinct. It washes out in about 20 shampoos. I used a color different from the one I always use yesterday and it's a little to red and brassy for me. Do I have to wait for it to wash out, or can I color on top of it with the natural I brown color I always use? The hot line will be open Monday, but I thought some of you might know the answer.