Stressed and worried...what else could it be?

I have a doctors appointment already but I had this pop up literally in a matter of hours. Same partner for 15 years. I've only ever notice this before when I was pregnant with my first daughter. I had something very similar happen and I don't know why but my doctor never swabbed it to see if it was herpes. I'm just curious if this has ever happened to anyone else and it turned out not to be herpes? I have very sensitive skin so I thought maybe it was an irritant?