The salon screwed up my hair...HELP?

I've been wanting to go darker with my hair from recently having it lightened, I am naturally a brunette. I tried the blond thing in the past few months but I wasn't really satisfied with it, thought my family said they loved it I still missed my natural hair color. A friend of mine referred me to a hair dresser, so I thought I was in good hands. The prices seemed reasonable, and though I like to be cheap, I do prefer quality. Well, I was given everything but quality, I am honestly surprised this person was given a license to do hair! I asked up-front what the cost would be, and I was told 50+ as my hair is thick and long. I said I wanted to go back to being a brunette and I said maybe low lights would be good. The atmosphere of the salon had this old-time feel to it, and the girl knew how to have interesting conversations, but when I looked at what was done to my hair I WAS SHOCKED! I felt like my hair was just ruined, and I asked "do you think this color will fade after washing?". I came to the salon expecting professional results and I felt like this girl just did something I would have done at home, it looked like the typical unprofessional mistake. MY HAIR TURED OUT PITCH BLACK! She had me fooled that it looked too dark because my hair was wet. When we came outside to look at it in the sunlight apparently the lighting inside was bad...I told her "honestly, this looks pitch black, I was aiming more for something like your hair" (which looked a nice chestnut brown). She decided to put in some light highlight to make the change less drastic, but I honestly was unsatisfied. I was sad what I looked in the mirror at home and I was embarrassed to be out in public after I came out of there. I am not sure what to do at this point, I left the place bewildered and i actually paid! I need an honest opinion as to what the best thing to do would be. I think coming in the next day for a refund would be the best solution. Any ideas???