I suspect an (UTI)URINARY TRACT INFECTION
So you should do
1. Urine for R/E, M/E
2. Urine for culture sensitivity.
Urine R/E, M/E will confirm the diagnosis.
Culture Sensitivity will help in choosing the proper antibiotic.
(not all anti biotic works on all bacteria, there may be resistance to particular anti biotic)
so you should consult a doctor.