What Causes Nausea Along With Pain In The Abdomen And On The Back?

Hello Doctor, I went to urgent care today and was told there was nothing abnormal. However, I still have troublesome symptoms. I was sick 3 days ago. Woke up with zero energy, chills, not feeling well. Today I work up feeling ill again. Since then my urine has been almost clear. Very abnormal for me. I feel slightly nauseous but have been hungry. When I eat, I feel nauseous again. I have abdominal pain. Some in the upper right and left back. I was told my urine specimen that was tested today was pristine . Also told that my vitals were normal. I ate dinner tonight and still not feeling well. Urine was clear even after taking a multivitamin which always makes my urine yellow. Aside from that I feel tired and somewhat dizzy with a mild pressure headache.