PLEASE HELP! IM FREAKING OUT

Okay so I have a weird lump on my vagina. It's on the outside of my vagina. It's on the outter lips? That's what I call it anyway. It only hurts sometimes but when it does decide to hurt it's pretty painful. I am going out of town tomorrow till Wednesday and not sure when I can get into a doctor. I'm scared. Idk what it is. But it swells and then it'll go down. Any ideas?!