It's hard to say what is most likely the cause of the bumps you've noticed, and keep in mind they can occur for reasons not related to STDs. There's no way we can sort out for you what's going on, so going to a clinic is the best bet. They can likely give you a pretty good idea just by looking, and of course can run any tests that might be indicated.
Most any healthcare provider should be fine. If you need a clinic referral, send your ZIP code to firstname.lastname@example.org
and we'll search for one.
Thanks and keep in touch to let us know how you're doing.