What Causes Vaginal Itching With Labia Minora Swelling And Discharge?

I'm fifteen. Height 1.56cm. Weight 60kg. I have a perfect medical history. Nothing related to this either. For about a couple of days i've been experiencing an itch in my genital area, and at first, i thought it was fine, maybe even because of the hot weather (38C averages), but today I got a look at it, and my labia minora is swollen and red. I can't identify any other prominent features, but I do have a thick-ish non-liquid discharge (white). I'm almost terrified. I'm not sexually active. I dont share undergarments. I do share towels, but only with family members. I have been getting a bit lazy with hygiene and i DO have a habit of keeping a moist towel around me for a minimum of half an hour everytime after I shower. I've narrowed it down to either a yeast infection or vulvovaginitis, and I am intending to wait it out and drink lots of water, and wear cotton pants, till it gets either better or worse. Is my decision a good one? And if not, what would be? Please reply asap as this isnt something that could really wait..