I woke up to the sight of really dark red rashes on my back. I'm trying to understand what exactly these could be a sign of because last night I and an escort only had a couple of drinks and made out but I don't remember being aggressive. I'm not sure why I got these rashes, although we use clean bedsheets and new condoms. He's even tested for HIV but I'm just not feeling so great after my skin is messing up today. Is this normal or are they serious enough to get checked?