Hi. I Have Had Left Sided Vaginal Irritation And Discomfort

Hi. I have had left sided vaginal irritation and discomfort (no pain or itching) but it feels swollen. Went to gyno and got tested for stds, yeast and BV. Said it smelled and looked like BV, so they gave me 5 day metronidazole gel. All tests (including BV) were negative. . Did not help and went back. Said it looked a little irritated with thin walls And that the smell was still there. Was retested and the tests again were negative but Dr put me on metrogel .75 for 5 days (again)! I'm worried! They said it wasn't a cyst or abscess because you would be able to feel a lump, not just generalized swelling and discomfort. When I looked inside I see swelling, no leisions, and it looks like part of the hymenal Remants are swollen on left side towards anus. What do you recommend? I am 25, never been pregnant. This is driving me crazy and has happened for a month!!!