I Have Lower Back Pain My Tailbone And More Lower

I have lower back pain my tailbone and more lower back pain on right hand side, I feel bloated and am urinating frequently. I went to the er yesterday because the pain was so bad they ran urine tests and said no signs of infection and sent me on my way... Could I have a kidney stone? Or would that show on a urine test? I am a diabetic but my numbers are in a good range my current a1c is 5.6. I have not had any injury or haven't done any heavy lifting. I'm 36yr old female have had a tubal ligation and a endometrial ablation 8 years ago.