The first thing to take into consideration is how much are your symptoms interfering with your ability to function optimally. It is difficult to know with the symptoms you have listed whether or not you have an eating disorder. For someone with an eating disorder, a full medical and physical exam is warranted to insure that your blood levels are intact and to rule out any medical issue that may be affecting your lack of appetite, such as thyroid issues, for example. You would also want to find out what could be causing your dizziness and back pain to rule out any serious medical conditions. If you have had a thorough medical exam including blood work, then it could be that your pains and appetite issues are mental health related, such as depression or eating disorder. A therapist, such as a psychologist, can help you figure out the reasons you have difficulty eating. It is very difficult to say how best to help you, especially without a firm question. I really would need more information to better help you. Good luck to you.