Hello,
It can be an infected hair follicle, boil, infected cyst or a herpetic lesion. Apply warm compresses and some topical antibiotics . If the symptoms persist then please get an examination done from a dermatologist as it may need oral antibiotics and drainage and herpes may need to be ruled out.
It is very difficult to precisely confirm a diagnosis without examination and investigations and the answer is based on the medical information provided. For exact diagnosis, you are requested to consult your doctor. I sincerely hope that helps. Take care and please do keep me posted on how you are doing.
Go back to your doctor and SHOW her the changes and let her take care of it...ESP if you are pregnant and it has pus coming out of it!