What Causes Low Pelvic Pain And Sharp Pain In Back?

hi im female age 56.for the past 7months i have had 6 lots of antibiotics due to possible urine infections.today i went for an ultrasound but the sonographer said all looked well although i have to wait 7 days for results.the symptoms i get are low pelvic pain and low back pain.im also getting sharp stabbing pains in my back passage,could this be piles.