these are vague and non-specific symptoms. unfortunately it would be impossible to blindly diagnose your friend based on such little information. this person should be seen by a medical provider so he/she can be properly examined diagnosed and treated -- three things that cannot be accomplished over the internet.
really bad stomach pain back shooting pains very bad headaches = what possibly? . i have a friend who's 17 and has had this going on for slightly over 2 weeks now and just wanted to try to help her maybe figure out what's wrong before going to the doctor