I have consistent kidney stones weekly/monthly but every time I go for a CT they don't show up, what is going on?

CT Stone Protocol. Some ct scans that are done, if not calibrated for thin cuts, may miss symptomatic stones. However, if you are having recurrent symptoms without any proven stones, then i'd look for other answers. Ct, done properly, is about 99% sensitive for stone. The only stones that don't show up on ct are Crixivan (indinavir) stones. If you take that medication, let your doctor know. If not, it's likely not stones.
Uric acid? Have you trapped any of the passed stones to submit for analysis? Some stones called uric acid stones are translucent on x-ray. Ct scan is a form of xr. If this is the case this is treatable. Another way is to collect 24 hour urine to see if your uric acid excretion in urine is excessive. This will also show other problems that you may have.