Why is this happening?! (Embarrassing)

Lexi
Okay.. So within the last couple days I've gotten these bumps on my vagina. (Not the hole, just the outside like where your underwear touches). They're pretty sore. There's no way possible I have an std.. So I'm assuming they're pimples. Which, that makes me feel dirty. I wash down there a lot of times twice a day.. I obviously wear clean underwear.. Why is this happening? I feel disgusting.. 
The boyfriend is gonna wanna mess around and I'm going to have to tell him no because I'm so majorly embarrassed..