I'm REALLY scared. Do I have genital herpes?

OK, number one you do NOT get herpes from a toilet seat and not much of anything else either. Second the vagina is an INTERNAL structure, if you sit on the toilet seat the vagina doesn't touch it. It is never a good idea to put perfumes etc around the vulva which is what the genitals and vaginal opening are called. I am going to take a wild guess you have developed a "pimple". Get a mirror and see what is going on.