I went to the doctor today with pain in my side/back, the doctor took a urine sample, it had 3+ blood in my urine, I was sent to the radiolog department for a CT scan to see if I had kidney stones, came back negative for stones, but they found a nodule on my lung close to my heart. What does this mean and what could it be? It was not there 2 weeks ago when they done the last CT scan. Please help!