What Causes Vaginal Rashes With Discharges And Odor During Menstruation?

hi, im an unmarried girl of age 28 yrs. im having a big problem that everytime during my monthly periods it happen to have red rashes around the vigina..or somewhat like allergic reaction..after my perods i happen to have smelly white light yellowish discharge which makes it really itchy and im so worried about my problen .pls kindly help me out and find solution to my problem