Abdominal Pain Extending To Back, Difficulty In Urination, Nausea. Normal Ultrasound, Blood Work. Appendicitis Recently Done. Help?

Hi my daughter has been in hospital for two weeks with abdominal pain which goes through to her back and is painful when her tummy is pressed and her back. She had her appendix removed 7 weeks ago in Turkey as they had ruptured and the poison affected her blood. She is having trouble urinating she can go but it takes her a long time, has been feeling nauseous and today started vomiting . The doctors yesterday started treating for pid with oral antibiotics but they are not sure that is the cause. She has had an ultrasound abdominal and a ct of her tummy and all looks fine. The pain is getting more severe and she has gone from feeling sick to vomiting and the pain is no better even though she is taking paracetamol , codeine , ibuprofen and oramoph and also anti sickness tablets. Her bloods are showing up clear, although one was slightly, but only slightly they say, for infection which they think could be left over from the appendix op. A small amount of fluid was seen on the ultrasound that shouldn t be there but ultrasound was carried out last Monday and CT last Wednesday. She has had an internal examination and that was extremely painful.