Sounds like a bacterial vaginally infection that you can get without intercourse - even from something as simple as diarrhea. The only way to cure it is see a Gynecologist ASAP. You need to be looked at and given antibiotics or it will get worse. Btw other people Can smell it and think you are unclean.. So go asap.
You must go see your doctor/gynecologist for a pelvic exam and diagnosis. It's okay to be scared, but don't put off seeing the doctor because of that. It's important to find out what is going on as soon as possible, so that you can receive proper treatment and not be in any more pain.
Take care :)