Hello, I am a 26 year old woman writing from France (although I am American) with a past history of kidney stones . About 10 days ago I started having back pain in the left mid back region and within this period I went to the hospital here in Paris, where they examened my urine and found traces of protein and blood. They sent me to get an ultrasound , the doctor said he didn t see any stones, but eventually a sand like substance. He told me to go see a general practitioner but I m actually more concerned now than before. I feel like I m going to spend a lot of money and be sent around in a circle. Any suggestions?