Trich probably is less likely, but that's because trich is a lot less common than BV. In regard to the irritation, imiquimod
) often does that wherever it is applied, as you already know, so that seems a good bet. From your description, herpes doesn't seem at all likely, but if your provider agrees the lesions look consistent with that diagnosis, appropriate testing can be done. If not, you shouldn't demand a blood test on your own; rely on your provider's judgment.