Depends if you have been with someone who has an std already?

not too my knowledge, but I can not gurantee this.

It's honestly impossible to generalise whether it is more likely to be an std or something else.

It could be an infected hair follicle, it could be a small boil, it could be a blister from an std.

The best thing to do would be to get your self checked for any std's anyway - it's nice to know you're healthy

if it is a single sore I would doubt it being an std, but if it is multiple sores then it could be - but it could just as easily be an allergic reaction to a change of washing powder, soap, shower gel, new clothing....

Also heat rash is another possibility.

Sorry there are just way too many possibilities to surmize.

Not necissarrily true the first of three stages og syphilis starts with a single sore. By the way it can eventually kill you but i think its treatable in its early stage so seek medical attention.

p.s. heres a fun fact syphilis is what many believe to have killed Al Capone after like 30 years though.