What Causes Diarrhea, Nausea And Lower Abdominal Pain?

For over a week I ve had abdominal pain. Wish I could pin point the area but it has been painful from middle radiating out mostly to right. Most significant being lower right hip but also a puffy tender feeling in upper rib area. Some gas but not much. First couple of days stools were very watery with last couple being just very loose and extremely light pale yellow. Have never had appendix out but had gallbladder removed 15 yrs ago. Appetite is poor with some nausea, no vomiting no significant fever just occasionally 99*.