I have gardnerella vaginalis??

Im 13 years old and I went to the doctor because my vagina has been itching and burning and raw,etc. Anyways I thought it sounded like a yeast infection but the doctor took a discharge and pee sample and said I have gardnerella vaginalis, which when I look it up online it keeps saying things like it could be an STD or things like that. Im not sexually active, so im really confused on this stuff. Can someone please explain this to me.