Increased discharge, different odor, no itching or burning, yeast infection? i start my period next week...

BV? Trich? STD?: Vaginal discharge with odor is most commonly due to bacterial vaginosis, i.e. overgrowth of mostly normal bacteria. Trichomonas, an STD, can do it; and STDs are more common in women with BV, especially at your age. Probably not yeast -- the main yeast symptom is irritation and itching, little discharge, no odor. You need to see a doctor or clinic, including STD testing.