Masturbation can cause vaginal infection?‏

I am a 25 years old girl who have masturbation for a couple of year, sometimes I even masturbate few times a day? Is it over masturbation? Over masturbation will affect my reproductive system and cause infertility in future? Besides, I remember when I am still a young girl who is so childish; I use some sharp objects to masturbate before. However, after masturbation, I don’t have pain, bleeding and vaginal infection in that moment, even till now. Is it means my reproductive system still function and not being infected? I am very worry; will this bring any infection or cause infertility in future? Will my reproductive system get harm without any sign and symptoms? This make me feel very guilty every times after masturbate.

Meanwhile, I am virgin, but recently, my vaginal and vulva parts feel itchy and have some yellowish vaginal discharge, especially few weeks before my menstrual period. I had already visited a doctor, she said it is just some vaginal infection. However, I seem didn’t recover after taking the medicine and applying the cream. I am worry this infection is it related to my previous way of manstrubation or it is just vaginal yeast infection?