Could this be a symptom of a STD/STI? (Pictures included)

I was getting changed after my shower and I noticed this smallish round crater like bump next to my vagina. There’s one one and It didn’t hurt or itch until I messed with it a little (trying to get an idea of what it was) I have a doctors appointment tomorrow but I’m really worried. 

This is the first time I’ve used this site so I’m still working out how to upload photos 

Here are the photos

Looks like ring worm. Easy to cure

Thank you for your reply!