What Causes Painful Bumps In Vagina With Pus?

Hi this is kind of embarrassing but im really worried. I got this painful red bump around my vagina. A couple days later it filled up with a sort of yellow puss and its been sort of leaking for a couple days now. Its kind of red and shiny now. There's a slight tingling feeling underneith that just started today. If it makes a difference both the bump and my period started around the same time. Im really scared this could be herpes- but i haven't had any sexual contact with anyone for at least 6 months now. The only possible way i could think of contracting herpes is from a towel that someone with herpes used or something like that. I have a doctors appointment on tuesday but whats your opinion on this?