HELP!!! STD? infection? normal? not normal?

I remember getting home and going to the bathroom when I noticed a bump on my inner labia...I don't know if this is important but I was wearing tight shorts and we went on a water ride at six flags so it may be like a rash? I had some thigh chaffing and it was all pretty normal...what what's the bump? It could be an STD but the thing is....I'm a virgin...and I have never had ANY sexual contact like oral, anal, or just kissing or touching genitals...it's not too big and it doesn't hurt I thought it looked like a pimple and started squeezing and when I put a bit of pressure on it it hurts! Should I be worried? I popped it and some pus came out and it was all gross...but I know that a lot of women have these glands/bumps that do that it's just mine looks a bit different and is near my clitoris...it's colored like my vaginal skin and isn't red...but I do share a razor with my mom who's been hooking up with tinder dates for like 3 days...so...what do I do? Should I be worried? (It only hurts when I touch it and when I popped it no blood came out and it isn't like itchy)