I have a large red sore on my pubic area about 1cm in size it popped up randomly when I woke up in the morning and at that time it was a little raised and hadent opened up I think scratched at it taking off the first layer of skin it has been 3 days since then and it has gone flat but the it is still red sore I have only had unprotected sex once and it was with my partner who hasn’t had sex with anyone else I am just worried this may be an std but from my research I can’t find any photos that look like what I have got I am just freaking out a bit.