Suggest Remedy For Tender Knot In Inner Labia

i recently discovered a knot on my inner labia ( i think thats what it is). Its on a fold almost near my vaginal opening. I noticed it while i was using the restroom and it was tender while wiping. Ever since finding this knot i have noticed more sensitivity around it and on it. It is underneath the skin and it is about the size of a small marable. I dont know if this could be of help but last week while playing basketball i notice my groin area hurting and i thought i had just pulled it by over doing it. The pain from that was horrible and just ended a couple of days before finding the knot. I am really scared on what this could be, if anyone has any insight on this please please please inform me! Thanks:)