Hi This Is Fairly Embarrassing For Me, But I Have

Hi this is fairly embarrassing for me, but I have not had health insurance for a while, so I'm unable to make a visit to my family doctor. I have been getting the blood-filled pimple-like sores on my labia for a few years now. I used to be afflicted with severe acne when I was a teen, so I thought that might be why, but now that I'm 23, my issues with acne have reduced significantly. Normally they don't bother me beyond mild discomfort, but some of them get fairly close to the "hole". I have PCOS and limited periods, but they do seem to occur more often during a menstrual cycle, and if they get near that hole, it's very uncomfortable to wear a tampon for any length of time. Is this something that I should be concerned with? I've not had sexual contact of any sort, intercourse or outercourse included, so it couldn't be an STD, could it?