This only started after my period also i'm breastfeeding and on microval?

A urinary bladder infection or urethritis are probable causes. Your gynecologist may be willing to prescribe an appropriate antibiotic without you're going for a urine culture&colony count as we often do for uncomplicated lower urinary tract infections in healthy young women. Remind the prescribing MD that you're breastfeeding so that a safe antibiotic will be prescribed.