I've been noticing that about 10 days or so around my period, an area of my vulva swells up and becomes sore. If I press that area, it hurts. The pain is mild and subsides in a day and is followed by milky discharge. The first time I noticed this was after I took a contraceptive Plan B pill, in February this year. It appeared after a week of taking the pill and it was pretty bad then. Since then, it happens once a month, and the pain is becoming milder each time. I assumed it was because of the pill so I let it go, but now I'm not so sure because it's been about 4 months. I am considering seeing a gynecologist.. but I need a second opinion as to why this could happen.