Freaking out

TMI:

So a few days ago when I went to work I think my panties were rubbing on me weird because they were super uncomfortable and just felt awkward. Well I have 1 pimple like bump that’s sore if you touch it on the lip right next to my clit and I’m trying to figure out if that’s what that could be from. It’s been a month since I’ve had sex. And I know if it’s herpes or anything of that nature it’d be more than 1 bump and more symptoms. I have no odd smells, no odd discharge, nothing to that nature other than that 1 bump that’s been there about a week. What should I do ??