UTI or Yeast Infection?

Hello, I am a 15 year old sexually inactive girl.

I was just wondering if I have a UTI or yeast infection? Here are my symptoms:

•Burning sensation when urinating

•white gunk between my vaginal lips

•heavy discharge

•pain inside of the uterus

•a smell?

•feeling of I didn't fully empty my bladder when I finish peeing

•sudden urges to urinate

•sudden urges to urinate only to urinate very little

Those are my main symptoms. I have checked and I don't have cloudy urine, dark urine, or blood in my urine. Occasionally I have dark/cloudy urine but it's very really when my eating habits aren't good. I drink a lot of water as well. If anyone knows what I have please tell me what I can do! I've been experiencing this for a while now.

How can I bring it up to my mother?

Also, how did I get it? I've never been sexually active?