Here you need to understand there can be various resiinnfor back pain and stomach pain. If you have pain only at back and not radiating to your legs as well no symptoms of numbness in legs then it can be mascular back pain. And if it is radiating to your legs with numbness or tingling or pulling feeling then it can be related to nerve compression with disc problem at your back. In both this conditions you need to visit orthopedic and physiotherapist. Here ortho will help with medication as well surgical option in sever cases and physiotherapist will guide you with exercise part as well some more treatment therapy to relax the soft tissues. You can also use hot and cold pack at home for further pain relief and relaxing soft tissues. Now for abdomen pain again there are couple of things you need to check. Is your periods are irregular? As well do you have digetion problem? Do you have acidity problem? Are you on any medication which can cause stomach upset? As per the answer you need to visit the doctor and evaluate your problem. You may need to do some test like ultrasound abdomen too. Go ahead if needed and as per the report take the treatment. Take care.