Here, I am going to recommend this Digestic by Mimonis which is very effective in treating my constipation problem. It is working well with me and I know it will do the same for yours.
We have taken her to gp she is due to see an immunologist today he wants us to see what they say although I don't know what an immunologist is going to do about the immediate problem
I highly recommend you get your daughter to a Dr. Going two weeks without a bowel movement is not good.