What Causes Vaginal Odor?

Hi

I am 19 years old. I have a really bad Vaginal odor I am a virgin so i know its not a sexually transmitted disease and its not yeast i am overweight and used to take provera 10mg for my irregular period if this helps at all ..some one said that maybe its like sweat in my v- area accumalating or something is this true i have asked my dr she tested me and said that every thing is normal but i dont think the odor should be this bad ... I also took a ph balance test and it came back normal ....also because of this i were panty liners everyday even when i am not on my menstrual cycle and have to carry wipes with me all the time and its just really frustrating to not understand your body ..Please Help !!! thank you Ps srry for making it soo long