Hi Goingtogetbetter,
I'd like to suggest that you call Beyondblue on 1300 22 4636 or Lifeline on 13 11 14 and ask for help and advice.
Somehow you need to reassure your daughter that everything will be okay. It may help to sit her down quietly, take her through some deep breathing exercises to help calm her down and encourage her to tell you what the problem is, while all trying to stay calm.
Maybe she needs to be held and reassured. Distractions might help her, put on a favourite movie, prepare her favourite snacks, reassure her everything is going to be okay.
If you do need to go out, encourage her to join you and take a change of clothes just in case they are needed.
If you are really concerned, see if there is a DR available close to you for an emergency visit or all into the hospital emergency department if she becomes really bad.
Hopefully some of this will help and you can get the help you need quickly.
Cheers for now from Dools