@Linkat,
Yes you should talk to the teacher.
It's possible that your daughter misunderstood what the teacher told her (but I doubt it), and so you should give her the opportunity to explain what happened.
Bad teachers are seldom evil, they are mostly just stupid. If your daughter misunderstood, then I bet the teacher will be able to explain in a way that you can accept (I base this on a belief derived from your interaction in this forum that your are not the type of mother who believes her kids no matter what).
I'm a huge fan of good teachers but a believer that too many teachers are not good, and I am betting that she will not be able to explain what appears to be an inconsistency.
Having said this, if some kids did finish the test, why couldn't your daughter and the others? Unless she did have a "special need," what's the excuse?
I'm reminded of an Algebra class I had in 11th grade. Our teacher gave us weekly tests and one week I broke three fingers in my right hand playing football. As I had to take the test left handed I was concerned I might not be able to finish it and spoke with the teacher beforehand. He told me not to worry as he could obviously see that my right hand was in a full cast and to do my best.
I made it through a little more than half of the questions when the bell rang, but I turned in the test paper confident of the understanding of the teacher.
The next day the test papers were returned to us and mine scored a 52% which signified that I had the correct answer for all 26 questions I answered. Never-the-less the wonderful Mr A. wrote beside the score the word "Pathetic!"
When I confronted him after class he responded "Oh please you could have finished the test."
Today, part of the story might have been that I called him a
dick and stormed out of the class, but back in the day that wasn't done. He was a dick though and so might your daughter's teacher be. There is no guarantee that confronting the teacher will make a difference, but at least you will have a good idea of the truth of the matter.