I have been having headaches for a month, lower back and abdominal pain for two weeks. Along with these I have a nausea feeling. the lower back pains are unbearable. I don't have uti cause I know what that is and I am wondering what could it be. I took a 800 mg ibuprofen and it took the pain a little but not completely. To explain the pain better it feels like I am going into labor but I'm not pregnant. Does anyone know what it could be?