Hi.. Welcome to HEALTHCARE MAGIC.. I have gone through your query and can understand your concerns.. As per your complain it seems that a round lump in vagina can be most probably a Bartholin s Cyst while can also be due to other causes like Inclusion cyst, Mullerian cyst,abscess etc.. It generally occurs when the glands present under the ucosa becomes clogged and infected or there is trauma to the glands or its ducts.. I would however suggest you to consult a Gynaecologist and get evaluated and a thorough clinical evaluation and biopsy can be done to confirm the cause.. Commonly the cysts are painless and harmless and no treatment is generally needed.. In case if there is infection and pain antibiotics, anti inflammatory painkillers and Sitz bath that is sitting in warm water tub can be advised.. Hope this information helps.. Regards..