You have my sympathy - and this is a common problem around now. It is too late for any child to do "last minute cramming" - the task now is to rebuild her confidence.
Do you have any practice papers left at home? If not, download a few of the Tutors 50 minute VR papers from here:
Get her do one every other day from now until the first test - more often if she is willing. Now for the clever bit ...
These papers are slightly easier than the real test, but don't tell your daughter that.
When she does them, don't use a timer - just make a note to yourself of the start time. If she gets to 50 minutes and seems to almost be at the end, allow up to 5 extra minutes - without telling her.
When you mark the papers, mark any that are wrong with just a "slash", not an "X". If she hasn't achieved at least 68/80 (or a score similar to the ones she was previously achieving), go back and turn a few of those "slashes" into ticks - just enough to get to a score she will be happy with.
Turn the remaining slashes into "Xs", and go through them with her if she is willing to do that. I suggest that the "Xs" should particularly be any vocab errors, because even at this stage a couple of new words in her lexicon could make a difference on the day.
All of this comes under the broad heading of being "economical with the truth". With a couple of good results under her belt, I think she will feel a lot more positive by next week.
Good luck! Let us know how she gets on.