Being sent home from hospital too early.

My son is in hospital and there is talk of sending him home very soon. When I say 'my son', I mean the complete strager I visit every day in hospital who now speaks with a very Royal British English accent 24/7, is still wearing exactly the same suit, white shirt and tie that he was wearing when he was admitted ten days ago (he normally never even wears a suit) and won't wear his normal clothes that I have taken in to the hospital because he claims they are not his clohes - that they belong to 'Norman Percy'. When I asked who Norman Percy was, he answered 'a normal person'. Instead of showing any signs of improvement since being admitted to the hospital, he has actually become worse and the British accent even more pronounced. He was admitted May 4th. Today is May 14th. Every single day I have asked to speak to a doctor but every time been told there was no doctor available. When I eventually spoke to a nurse, he was amazed to discover that the person who used to be my son is Australian, not English. Yesterday another nurse told me my son could be releasd from hospital next week.This would be a disaster as he lives alone and I live in a small one bedroom unit in a retirement village so he wouldn't be able to live with me.His diagnosis is bi-polar disorder which he has lived with for many years but what is happening now has never happened before, He has turned into another person completely and I am very worried.
My question is this. Can anyone advise me of someone I could see re getting help in keeping my son in hospital until he is 'himself' again, before being sent home? Is there a Body or Society I can report the hospital to if he is released prematurely?