What Causes Blood In Urine While Suffering From Sinusitis?

I just experienced blood in my urine. That has never happened before, ever! I have been ill with a bad sinus infection, and sore throat, which has now moved into my bronchial tubes. The mucus I am coughing up is thin an fairly clear, and not thick and yellow or green. However, I donated a kidney to my daughter on June 5, 1998 to my 15 year old daughter, so would like to be careful. I can make a doctor's appointment for tomorrow, and will check to see if urine continues to have blood in it. I am experiencing no other pains anywhere else, other than in my left sinus.