I have a sore on my vulva that felt like a blister, finally popped a few days ago, but its still oozing. what is this? had a full std scan was neg.

Lesion: This could be an infected abscess, boil or cyst, all of which may not be std in nature. If it is troubling you and not going away, get eval from your gyn. Best wishes.

Probably not if...: If this popped blister's one only, of first time, slowly getting better, but left behind a tiny palpable painless nodule, it could be just a tiny infected, now spontaneously ruptured sebaceous cyst like a pimple, because herpes usually comes with a cluster of blisters, less likely just single one. So, just watch how it will resolve. It bounds to recur. If in doubt, watch for std due to high at 24.