I have a green discharge from my penis but i'm a virgin and it doesn't hurt or even itches could it be std?

Oral sex?: Oral sex can transmit STD"s. What else have you done that makes an STD a possibility? Anyway, a green discharge is certainly not normal and you need to see a doctor as soon as possible to get diagnosed and treated. It may not be an std but that does not mean it is not an infection that needs medication.

Balanitis?: I agree with Dr. Rhoads. If you've had no sex of any kind with another person, including oral, it can't be an STD. Are you circumcised? If uncircumcised, I would guess you might have a bacterial or yeast infection under your foreskin. (The medical term for that is balanitis.) Most important is to see a doctor right away!