I keep having this vaginal itch sometimes dischagei got tested for all stds and they all were nnegative i do have herpes type 2 can that be the cause?

Genital herpes: This is often manifested by painful ulcerations and seldom by itching alone, but anything is possible. More likely that you may be having a local reaction to something you are coming in contact with (allergy to tampons, lotions, contraceptive jellies, condoms, semen, and so on and so on). This needs to be worked out by examination and tests on the discharge and cannot comment without seeing these.