I've just logged onto the Chester Uni website and on the student support page they mention an 'Access to Learning Fund'. It says that this fund is availble to enrolled students facing extreme financial hardship (Basically what you are facing) - You need to contact Student welfare, try this number 01244 511550 and ask for more info. I am not exactly how it would work with you being on a placement year but at the end of the day dont quieten down, explain to them that you need funding as it could mean you may have to give up your course. Really play it up and let them know about it. You have too.
Get back in touch with your local LEA immediately, if there is any chance of some extra funding then find out about it and try and get it!
Get back in touch with your lecturer immediately and lay down the score, your facing some financial difficulty and you really need to know how long they will be in allocating you your placement. You havent got the time or money to mess about, I would start looking for a job as a precaution but approach your lecturer first.
I know you dont want to talk to your parents about this but I think that you have hit a really bad point if you cant even afford food and whilst i know they wont be impressed i am sure they can help you that little bit more, even an extra £1 wuold be better than what you have at the moment. Remeber that the rent is due before your loan, at the moment you have no means to pay for that. If you gave your parent prior notice then I am sure they would rally around to help even if they werent happy about it. You could approach your landlord and ask for an extension but then you will owe double and your landlord isnt going to be as lenient on your repayments as your parents would be.
Is any of this helping??