Suggest Treatment For The Red Spots On Vagina

4 months ago i noticed a red spot near the vulva....it isnt raised, its not a blister or anything...this was noticed a couple of days 2 days after intercourse...only hurts when it is pressed on...been to gyno 2 times and she said didnt look like an ulcer or blister but irritation of skin....it is still there and there are a few raised spots around it but not red or anything and not painful...i have std test and all neg ..she gave yeast infection meds and cream but still there...what could be going on because it is really bothering me that it won't go away