I have smelly yellowish vaginal discharge and sores on my vagina and i don't have a std?

Vaginal discharge: In order to diagnose this accurately you must be seen and examined. This may be bacterial vaginosis (which does not require prior sexual contact), but how do you know you do not have an STD? The sores on your vaginal area may be herpes, but again you must be examined to be correctly evaluated. Best wishes.

Vaginal infection: You have a vaginal infection and need to see a MD for evaluation and treatment.