I have knee replacement on 8/3. That is doing fine. But now for the second time in 6,weeks I am having difficulty urinating. The first time it happened i thought it was a uti, called dr and got RX for antibiotic. It cleared up. Now since day before yesterday I have the same feeling of retention, not completly emptying my bladder. Urgency but little to no urine after several attempts and pusing fluids I am able to void but still feel bladder has not emptied. I did not have a foley during surgery and was able to void fine the first 3 weeks after surgery. I have been as active as possible, doing all the PT that was ordered. I am a female. I have also noted a few tiny clots and slight tinge of blood. I started taking OTC AZO but it doesn t seem to have helped.