They will have a complaints proceedure and your local council will probably employ someone who's job it is to investigate complaints. Contact your local council to find out what the proceedure is.
I work for Social Services (please dont hate me lol!

)and Im sorry you had such a bad experience. please do make a complaint, that's the only way things will ever get changed. I always encourage the people i work with to complain when processes and proceedures are unfair, go for it, other people in a similar position (and probably many people who work for social services - most of us do actually care)will thank you for it! xx