Go back and complain. Go back, see the manager, show the manage the picture, and complain. And 'phone their customer services too.
This happened to me at another salon. I stopped the cheque, and 'phoned and explained why. I didn't need to stop the cheque, as it turned out, because they returned it anyway, and were very apologetic. While they couldn't do anything about the hair length, they did offer me a sitting with their top colourist. So, their customer service was good ....
That, of course, may not be what you want, but I tell you this so that you know what sort of level of (grovelling) apology you are due.
Really, if you went in with a picture, to somewhere that well-known, they shouldn't be messing around with your hair to this degree.