Anorexia is frighteningly quick. I've found support through Anorexia Bulimia Care (ABC) a smaller charity than Beat but much more expert and you get to talk to either helpline advisers or parents who have been in the same position and can advise on recovery etc (link to helpline below) - as @myrtleWilson points out one minute you know nothing and next you need to become expert in a shocking array of symptoms and behaviours.
My DD17 is the other end of the scale with BED - binge eating disorder, and body dysmorphia. She went into school today, day 1 year 13, and was immediately stopped and told off about her dress - so of course, scrutiny of her appearance nearly tipped her over the edge so we've had lots of tears tonight but she is so brave getting reading to do it all again tomorrow.
She's been under CAMHS for 2 years and they have been worse than useless, I feel sick thinking about it. When I persuaded her to explain how she felt about herself to the psychiatrist, saying she hated her skin, her face, her eyes etc, the woman laughed and pointed at her saying well you have got spots, why don't you wear more make up. She's been refused referral to the Michael Rutter clinic (we are in the South East), she can't self refer at this age and when I spoke to someone at the Priory I just got the impression I was talking to a salesman (I was).
Longer term we will look for another therapist but DD wants to try to complete year 13 so I just take one day at a time. We do have a paediatrician and another charity support us, even a local authority support worker to help with school but CAMHS refused to deal with any of them, and our GP sided with CAMHS. I'm glad to see some of you have had good experiences of getting treatment quickly.
I agree that starting uni can exacerbate any anxiety/MH issues and a friend's daughter came back at Easter having lost a lot of weight. Sort of thing you could talk through with the advisers at ABC:
www.anorexiabulimiacare.org.uk
(not on commission, just a fan)