Recurrent UTI, pcod, lower back pain.

Married since 1 year 4 months, immediately after marriage had UTI( ecoli & Klebsiella significant growth ) took nitrofurantoin for 7 days. Then in between 3-4 had symptoms of UTI, in view of normal urine examination not taken antibiotics. But last month had dysuria and increased frequency,mild lower abdomen pain, urine routine was normal, culture showed  significant Klebsiella growth. Asked nephrology doctor he advised to take cefuroxime according to sensitivity report and vaginal examination to rule out infection, USG abdomen. I went to gynecology doctor, she advised AF kit for husband. Symptoms reduced with antibiotic but when I got periods, bleeding had sweet and sour smell. Even after bleeding stopped I am having  mild lower back pain. I never had  excessive or foul smelling discharge Pv examination not done Is it due to vaginal infection? Can I plan for pregnancy?