Pelvic and lower back and sudden urge to urinate. i tested to see if i have a uti or a virginal infection and both negative. loose stool and nausea. ?

See below: Unfortunately, it is not possible to make an accurate diagnosis based solely on the limited history and information provided. There are certainly are quite a number of potential problems arising from either the urinary, female reproductive, or gastrointestinal tracts that could cause your symptoms ranging from a benign, self-limiting to potentially a more serious problem. Recommend MD evaluation.