Hi and welcome to the boarRAB. We would love to help you but in order to do that we would need additional information. Back pain can be a symptom for many different things such as: bladder or kidney infection, female problems, pulled muscle, etc. The symptoms you have provided are not enough for us to help you.
I would also think after two weeks she might want to follow up with a doctor since it could be a symptom of alot things.