Bleeding between periods. Urine culture.

I m suffering from vaginal infection from one year... Also taking treatment from one year...done cbc, vdrl, urine culture... E coli found in urine culture... Taken nitrofuranation, Cephalexin, Levofloxacin, amikacin injections, fluconazole 150 doses, but no improvement...sometime pale yellowish and sometime white discharge come with itching in vagina. After tht my gynae gave me vaginal suppositories - (clindamycin phosphate clotrimazole and metronidazole), and tab candiforce, one time use of ticonazole vaginal gel..after tht metrogyl and doxycycline tab If feels like better from previous itching and discharge. But my periods started on 12th may evening and stops on 17th may...NOW ON 24TH MAY DISCHARGE OF BROWN COLOR COMES AND TODAY i.e. On 25th may bleeding occurs... I m tensed... Plz tell me what is the reason...low back pain with left leg pain also there... Plz help me... Wht happend to me... I m stressed...