What Causes A Round Growth Inside The Vagina And How To Treat It?

I have found a round growth inside my vagina. Its probably the size of a medium size marble. I also have a little burning and iritation. I thought I might be getting a yeast infection so I bought some otc medicine and that is how I found the growth. I do not have medical insurance at this time what is your thoughts on what it could be and how should I proceed in having it checked out.