Someone help me! I have reason to believe that I have chlamydia. What do I do?

I received a phone call from a friend the other day, and he told me that I may have been exposed to chlamydia. What do I do? Can I make a doctor appointment without my parents supervision? (I'm 17 years old) And I don't want my parents to find out about this. Also, is chlamydia treatable? What can I do? Someone please help me.