Hi,
I don't think she was trying to bite you, she would probably much rather try and run away than sit there and try to bite you, also if she is 8cm, you would know if she was biting you as her fangs are already a good size. It would also have looked upset or frantic.
T's do all sorts of things with their fangs, so who knows what it was up to, I have read about a T that lost all it's legs in a bad molt and walked around for something like a year using only it's fangs.
Although curly's are docile, they are still Tarantula's and can most certainly bite if they need or want to.