Too Dark

Please help!! I had been using temporary colors on my hair for a few years now and finally decided to go to a permanent as it seemed like the color was not covering the gray good enough for me. I was told to use the same color (compliments - light ash brown) in the permanent. My hair is medium brown naturally. The color made the top and crown of my hair very light and reddish and brown on the mid to bottom sections. I went back to the beauty supply and the manager told me to use a medium neutral brown (clairol - permanent color) and put it just on the crown and top for 40 minutes then pull through the rest for 5 minutes. The result was almost black hair on the top and around my face and lighter underneath and on the rest. All I want is my natural hair color back!!! I don't know how to do this. Can you give me some help? Should I try to lighten the hair on top and aound my face? I used the name Elvira to log in because theat is what people are calling me!! (which I hate). I was going for a nice chestnut brown. Please advise!