I seem to remember you asking about developmental issues before, am I wrong? I did not look back. If you have had minor concerns, and more than a few, especially about langague develpment and the like, just go get an evaluation and put an end to the wondering. Evaluation is a win-win. You either walk out the door knowing what to do to help, or you walk out the door knowing you don't have anything to worry about.
What you describe could be echolalic speech, or it could be that she is stuck on a ridgid idea, or it could be related to central audio processing...many things, and it could be nothing. I would want to know when she is young enough to help her easily, and that time is right now.
You should call and make an appointment with a speech therapist. She may qualify for some services through your school district, but these are almost never enough, so go private first, then pick up what ever you can through the school. A school is only required to make your child functional, and you want to maximize her potential, huge difference. Get what you can for free, but be sure that you know every thing she needs to be all that she can, and see that she gets the rest.
If this is more than langague based, see a Developmental Pediatrician. You will know that you have missed nothing if you see one, and you will not have to wonder any more. They can be found at all major Childrens hospitals.
Good luck! Never wait on Development, and never spend time wondering IF your child needs help. Get the evaluation, and find out for sure. Children have too much to lose, and so much to gain if you should be worried...so stop worrying, and find out.
M.