Brief Answer:
urinalysis, urine culture, antibiogram and antibiotics

Detailed Answer:
Hello,

since it's not the first time you've got a UTI and you can recognize the symptoms, the diagnosis is probably right. Urgency and frequency are the most common symptoms. A urinalysis will probably detect the presence of white blood cells, nitrates, bacteria. Sometimes red blood cells are also seen. The urine culture will certify the presence of bacteria and identify their species. Finally the antibiogram will identify the best antibiotic for your case.

Empiric antibiotic treatment depends on previous antibiotic exposure (particularly during the last 3-4 months), recent hospitalization, immune status, allergic history, etc. Levofloxacin is a potent antibiotic and will deal with most pathogens of the community (unless they're resistant due to previous exposure to hospital strains or to antibiotics).

Having started levofloxacin will reduce the likelihood of a positive urine culture. The lab has to be informed about levofloxacin (they might give the culture some more time to thrive). If you don't get better after a couple of pills then a resistant strain has to be suspected. Treatment of bladder infection will quinolones (like levofloxacin) does not require more than 3 days in most cases.

An ultrasound scan of the urinary tract wouldn't go amiss, since recurrent infections may have an anatomically identifiable cause.

I hope you find my comments helpful!
Kind Regards!

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