Does this sound like kidney stones?

I'm a 25 yr old female. I've been having problems with frequent urination and urgency. My urologist thought it was overactive bladder. I was put on medication and that problem seemed to slow down. Then I started having other problems. I would get these weird muscle spasms in my vagina and urethra. And now I experience pain in my back and side. I went back to the dr and they found a trace of blood in my urine. So now she thinks it's kidney stones and I'm scared to death. The only thing I ever drink is water so now I'm drinking more to try to flush it out. I go for an ultrasound on Friday and am scared to death. I'm not ready to go through this.