@revelette,
She did try to call Trayvon back, she didn't get an answer. He wasn't staying at home, so maybe she didn't know who else to call. And Trayvon's body wasn't identified for a while.
She definitely didn't want to be on the witness stand. If her testimony wasn't so crucial, I doubt the state would have put her on, because she doesn't present well, but she has information that no one else can supply.
On the issue of who was screaming for help, she wasn't definite, but she also didn't say that it didn't sound like Martin--she clearly thought it "could be" Trayvon.
On other points, she was more helpful to the state. She describes Martin as being concerned about this guy who was following him. From her description, Zimmerman did not identify himself to Martin, and it sounds like he was the one who approached Martin, not the other way around, and his tone toward Martin was challenging. Those are important factors in considering whether Zimmerman provoked an altercation, and why Martin might have reacted defensively.
I think this witness was trying to answer the questions, but she really doesn't seem to realize the importance of the exact words she uses in the context of this case--her testimony is
very important in this case and she doesn't show much awareness of that, or patience for the process--and her speech is also difficult to understand at times. She can't understand what all the nit-picking is about, and she seems to just find it all tedious, and stressful, and frustrating, and she gets clearly hostile. It's hard to know how the jurors might react to someone like that--regardless of what she says.
It will be interesting to see how she does on cross-examination tomorrow, and on re-direct. She's an unsophisticated high school kid, and she's nervous about being on the stand, and having her every word challenged, and she reacts in a somewhat refreshingly honest and spontaneous manner with her anger and annoyance. She's obviously not the sort of witness the state would wish for, but they need her. Maybe she'll do a little better after a good night's sleep.