I'm not a doctor by any means...and since you are a little hesitant not to take her back for xrays....I would maybe wait a couple days to see how she does. Sometimes "jumping the gun" on injuries,is a common thing, especially while playing sports.
My daughters are BIG basketball players. Especially my oldest, she plays on 1 traveling team , 2 high school feeder teams, and will be doing our school team come Septemeber. She sometimes plays against BIG Highschoolers or even BIG girls in her own division. (she is going into 7th grade) They play tough, rough, and there is constant body contact that goes on while driving into the basket. She has had her share of injuries. I have learned to wait a couple days to see how she does, instead of running to the ER everytime she gets hurt. (obviously for really bad injuries we go in). Recently she twisted her ankle so bad, I swore she broke it, she couldn't walk on it at all! Still turned out to just be a bad sprain, and although I felt better knowing...I hated spending the 5 hrs. in ER and the money...to be told it was sprained. In hines sight, I should have waited till the next day, because it was already feeling better by then....I would have saved a trip if I just waited a day. I would have made a different decision.
Now in your daughter's case, due to the fact that you feel she might be a little overly sensitive to pain. (which does legitimately happen but is a little misfortunate when you have a child in sports)I personally would wait 2 days. If it still hurts JUST as bad or worse, or there is some sort of swelling or she can't pick anything up...then take her in. If she seems to still be doing some common activity, or is actually getting a bit better...then wait it out. I do know there are tiny bones in the wrist, and they do break easily, BUT a lot of time, sprains mimic possible broken bones. Sometimes hurting even worse.
I don't think you should totally put it off, and if you are really concerned then take her in right away. But, if you are a little hesitant, (especially with her maybe low threshold for pain) then wait a little and see how she does. Even though she won't use the hand, really pay attention and see if she does little movements here and there that probably wouldn't be possible if she had broken it.
I don't know, I'm probably not much help. Just thought I'd give my opinion from a mom who has three daughters that play competitive sports and get injuries similar to your daughter.
Good Luck
p.s. I just reread your comment. I would think that if her forearm hurts and not even her wrist, it's probably just a sprain. If you put your wrist back, you feel the pull of the muscle on your forearm. Imagine it being pulled back hard, it would pull that forearm muscle too. I would bet on just a sprain after re reading what you posted. I would definetly just keep an eye on her, especially since it's not even her wrist that hurts.