MY daughter has been sick for 3 weeks with severe headache, dizziness, inability to walk on her own, nausea and vomiting. She was hospitalized last week and a spinal tap, mri, mra, and ct scan were done and all came back negative. All blood tests, saliva tests, and mucus tests also negative. She has no fever but seems to be getting worse. She has had a few moments of improvement but then the headache comes back and kicks her in the teeth. She is 18 years old and missed her finals at school because of this. When school starts back she needs to take them but is not in any shape to do so now. Her doctor mentioned the flu shot may have caused this. Has anyone got any information that would help me get her diagnosed? We are afraid for her and worried that this will only get worse. Any help you have will be greatly appreciated!