Hi there ~
I understand your concerns. I believe that you are not supposed to remove any stents by yourself. I also wonder why you would feel the necessity to do so. I wonder if you have consulted the doctor that put your ureteral stent in? If not, I strongly advise you to consult your doctor and go in for a follow up appointment. If it is pain that is making you feel that the reason for it is the ureteral stent please discuss this with your doctor. The ureteral stent, however is not very likely to be the cause of your pain. I hope this helps relieve your anxiety
Take care and have a lovely day!