Brief Answer:
further evaluation needed...

Detailed Answer:
Hello and Welcome to 'Ask A Doctor' service...
I've gone through your query in details...
I can understand your concerns...

Well, at this outset, there could be several possible causes, starting from a Urinary tract infection, kidney/ureteric stone, prostatic or some other pathologies...The fact that you're diabetic, warrants further thorough evaluation (not necessarily there has to be any bad odour) as an underlying infection may go unnoticed and can complicate it further...

To conclude the diagnosis, a thorough evaluation by your Physician/Urologist along with a few relevant investigations are necessary (namely Urine routine microscopy, culture sensitivity assay, Ultrasound KUB and prostate) to look into it further...management can be done based on the findings...

Please discuss this with your doctor and proceed further...

Meanwhile, please drink plenty of water (around10 cups per day at least) and cranberry juice to help relieving the symptoms...Avoid irritant foods like too much coffee, tea and carbonated drinks, some acidic fruits i.e. oranges, grapefruits, limes, spicy foods for the time being.

Let me know if I can assist you further.

Take Care
Kind Regards

---