Hug.
Huge gentle hug and patting your back (in a completely not weird from a stranger on the internet way).
You need a hug. And that's first before anything. You need some looking after yourself, you're giving everything you've got and a bit more besides, and you're running on empty. You poor thing.
One thing would be, can you ask to talk to a doctor privately/ without DD. And then lay it on them, just like you've said here. You feel they thought they'd help her because it wouldn't take long, and for the first time in a VERY long time, it seemed that she was being attended to by medics, by experts, by more than just her mum... And now, because it's not happening quickly, it seems to you that the medics have given up and handed all responsibility for your DD's health and condition, right back to you.
Its not ok. And you can't cope.
Oh you poor love. I wish I could do more x