Hello Dr. Grief. The past couple days ive been having really deep pulsating type pain on my right low flank side about a month ago i became coumiden toxic with an INR of 120 with similar pain accompanied by blood in my urine with similar pain. (this feels different/deeper and an increased urgency of urination is noted bit no burning or remarkable coloration) no stones, or infection was present last month via cat scan, CBC and urinalisis. Everytime have complained abut this discomfort and had the standard test i come back negative for stones. I have a history of Factor V, Kidney Stones , and Renal Cholic. Any idea what could be causing this ?