bad decision on my part!

Really bad decision, as I am going to a wedding next week and i was passing the supercuts in Norwich I decided to drop in for a trim to neaten up my split ends. The staff seemed confident and professional enough and I don't get my hair cut alot so I didn't think anything was amiss. I paid £20.95 for a wash and trim (as getting it blow dried took the price up to £32.95 I decided against that option - the only good decision I made!) I was served by lainey who seemed cheerful and who snipped off my hair with vigor. I asked that she take as little as possible off the length and she confirmed she'd take off an inch. She didn't - she took of about 5 inches - my nearly waist length hair is now shoulder length which I'm gutted about. I thought she was snipping away very fast, but assumed she knew what she was doing and after the first cut I actually said what would you do if I said you'd cut too much off, to which she replied she'd be very awkward as it was too late not to continue - I trusted she knew what she was doing. When I got home I had a had a proper look - the two sides of my head were cut to over an inch difference in length, the whole way round my head there were chunks of longer hair she'd missed, the whole cut was jagged and like steps had been cut into my hair unevenly all the way round. It hadn't been so noticeable wet, but dry it was rather spectacular. I ended up having to go to another(good!) hair dresser to get it fixed (at additional cost of course) and she said she couldn't work out quite work out how lainey had managed to cut it SO badly - she had a hard time fixing it, and in doing so had to take off more length, but at least it doesn't look quite so much like someone has been hacking at my hair with an axe now... Not a great experience really and very disappointed. For £20 I would expect a decent trim and I got a disaster!