If you had a catheter there is always a chance for a UTI. In addition, bacteria can exist in the urinary tract without causing a UTI. My guess is that your no longer on Sprio and you might have cut back the amount of water your drinking. Going regularly helps keep the bacteria out and if you go for a long time without peeing, it's an invitation for a UTI. It also possible the last antibiotic didn't target everything and your fighting the same infection. It's important to take all the medication as directed and do any follow up the doctor might request as the prostate makes it more difficult to treat infection than in a CIS female.
One other mention. If you had kidney stones, it's possible you may not normally drink enough water. In that case, get a measure cup or mug and make sure you drink enough containers to get at least the minimum amount of water - normally about half a gallon a day. My boss had kidney stone issues and his solution was to carry a half gallon insulated jug that he had to empty each day along with any other fluid intake he might have.