Bump on vagina

This is so awkward and disgusting but I'm in so much pain and so desperate. I'm 17 and I'm not sexually active but I do sometimes masturbate (how awkward). Lately (few months), I've decided to wear panty liners all the time. I just don't like the feeling of discharge and all that in my underwear so I wear panty liners. about two weeks ago, a large quarter size bump developed on the outside of my vagina sort of near my bikini line. it ached for a few days then later it ached and BURNED as if it was a scratch or wound of some sort. it has come to the point where I have to sit and stand it certain ways to not be in pain. Today, a little bit of yellow liquid (im assuming puss) came out of it. but not much. it's still tender and hard and burns. Besides that bump, a small pea size pimple also popped up out of nowhere near my genitals where the anus and vagina meet. that one is tough but small and hurts a lot. what do you think is the cause for both of these? is it the panty liners? and what can I do to make them go away?!! also I'd like to stay away from the doctor bc I'm really embarrassed. I'm in so much pain, HELPPPP PLEASEEE!!!