Ritalin kids symptoms and conditions

My 9-yr-old daughter was just prescribed Adderall for a one-month trial period. The first day was incredible. She was such a joy to be around. It was like I had my little girl back. She has been so trying for so long that I was just ecstatic. Although she did suffer from a bellyache throughout the day, which I hope will subside. The next day was not as wonderful. She was still a little hyperactive but her concentration was still improved and she was on her best behavior all day. The third day was almost as good as the first day, but that night she came into our room saying she heard voices whispering. When I asked her what they were saying she couldn't tell me what was said but was very scared. I have been distraught ever since. Is this indicating she does not have ADHD or is it a side effect from the medication?

Please help, as I don't want her to continue on this medication if her mental stability will be sacrificed.