need advice! ingrown hair possibly??

I am sexually active before my boyfriend and I started dating, he was messing around with this one girl who frequently had sex with multiple people and she says clean (she got tested a few months ago) BUT I don't think it's herpes because the bump doesn't resemble herpes. it's a single bump instead of multiple little lesions and it doesn't burn and only hurts a little if touched too hard. 

I think it's an ingrown hair I hadn't shaved in a week before today and it wasn't there before today, at least to my knowledge. what do you ladies think?

EDIT: discovered it hurts when I have underwear on but I think that's just because the edge of the underwear sits right on the bump. I think the friction is irritating it.