I know its scary, but try and relax.
Your whole world won't crash in even if you do have an std, I promise.
You can find clinics near you by googling your state and std clinics, or calling your local health dept (assuming you are in the US).
If you aren't, let us know where you live, and we can try and help you find some.
If you are a college student, your college might have a student health, and you could also go there.
Aj
you are asking a lot of questions that can really be answered with out more information. First where do you live?