However, you should definitely be evaluated by a doctor or other health care provider.
It could simply be a small abscess
, which is bacterial and not an std
; however things like herpes
, etc. Need to be ruled out.
If you are uninsured there are many free clinics that provide std testing; they will be able to tell you if you are dealing with an std or something as simple as a pimple!
my last bit of advice, please remember to always wear condoms