Lol where do you guys get your sex education from? Try googling some actual stats. There aren't that many people with HIV in general (around 1/700 in Ontario), and the majority of those are gay men and needle drug users. The vast majority of people with HIV are on meds that prevent transmission. Even if you have unprotected sex with someone with HIV and not on meds, the odds of catching it from a single encounter are 1/2500 for a male doing vaginal sex. You didn't even fuck her, it was just a PS, so there's literally a one in a billion chance (maybe even lower) that you caught HIV.