Suggest Treatment For Bacterial Vaginosis

hi im 15 and i think im suffering from bacterial vaginosis but not 100% sure because when i was tested for it the results came back negative. I've had a discharge for about 3/4 years now and its changed since ive started my period. Ive had a heavier discharge, it's changed in colour and its got a fishy odor and my labia majoras are red. Is this bacterial vaginosis? if so why did my results come back negative? and whats the best cure for it?