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You might most likely be having vaginal cyst. Vaginal cysts usually don't need to be treated. Often they will remain small and not cause any problems. To relieve any discomfort you're having from a vaginal cyst, sit in a bathtub filled with a few inches of warm water (called a sitz bath) several times a day for three or four days. it's also possible to have surgery to remove the entire cyst if you're very uncomfortable or the cyst keeps returning. Cysts that are treated with surgery usually don't come back. You must consult a Gynaecologist and get the cyst examined, if you wish to get it removed by surgery you can discuss about it with a gynaecologist and proceed for the same.
Hope this helps. feel free to ask if you have any further questions.