My initial thought was that you had another kidney stone, but then you stated additional tests show that you do not have another stone. Any irritation from your stone in Dec 2015 should have been healed by now too. I'm not sure about your continued irritation, but I wonder if you may have another stone that for some reason, hasn't been detected yet in all the tests you've had. Regarding your continued urge to urinate, I wonder if your doctor put you on some drug like Flow Max after your previous stone, and that is causing you to urinate more. You did not say anything about meds except you take/took antibiotics. Just asking if that's a possibility? After all the years and all the stones that I have dealt with, well over 30 of each, the only time that I ever dealt with anything like what you're describing is when I had another stone, immediately following the first stone in, if you will, "series" of two or more stones. Please let us know what you find out and how you are doing and make out on this problem.