Thank you for posting your query.
It may be a furuncle
that can occur elsewhere on your body. Kindly rule out Diabetes
Mallitus. You approach your surgeon and he/she will give appropriate antibiotics to control the further spread and for the subsidence of existing lesion. Some surgeon would prefer to go for a culture test from the pus or discharge and antibiotics can be selected according to the sensitivity of organism.
Another possibility is Bartholin's abscess which will be located on the lower third of the labium majus and pointing towards the inner aspect of vestibule of vulva
You surgeon will be able to guide you properly for the total cure.
Get well soon.