i am an 18 year old girl and while masturbating i discovered a lump inside of my vagina about 2-3 nches in. it is about the size of a penny and then some, round, firm, smooth and painless in general. however, when i try to masturbate with anything besides my fingers it hurts because they can t maneuver around it. this may or may not be related. also, i am not sexually involved with anyone so i can imagine stds being out of the question. can you tell me what this might be and if it is serious enough to go to thhe doctor for?