Thanks for the query.
According to your symptoms - vaginal little greenish discharge, lesions present on the external genitalia, there is possibility of trichomonial infection.
The positive points for this are:
-Sometimes single diagnostic test with less sensitivity may not detect trichomonial infection.
So better to go for two tests, among them one should be culture and sensitivity.
Reference: WWW.WWWW.WW -Vaginal infection
sometimes can occur by skin to skin contact, through tampon usage, sharing the rest rooms etc. apart form intercourse.
So better to take one course of broad spectrum antibiotics including drugs against anaerobic organisms. This can help possibly.
long term effects when treated early and properly.
Hope I have answered your query. I will be available to answer your follow up queries. If you are satisfied with all my answer, please rate the answer after closing the discussion.