If you're still having trouble with this, here's my advice:
First off, for something to be wrong this long means something is almost certainly going on and you need to see a gynecologist. You should be seeing one at least once every year, anyway, if only for a checkup. Seeing a gynecologist at this time of your life is routine so don't worry about your parents jumping to conclusions.
As you are above the age of 16 Doctor/Patient Confidentiality law does apply (in America, at least) and the doctor cannot discuss your visit with anyone without your written permission. (If they do they can loose their license, at minimum.) Your parents do not have the right to be in the room with you if you do not give them permission, and they do not have to know about anything that happens in that room unless you give written permission for them to be informed. Its your body, you have a right to privacy.
Let the gynecologist know what has been happening, and don't be afraid to ask any other questions you may have. (Believe me, anything you could imagine asking they've already heard and/or seen. Don't worry about surprising them with weird questions.)
Even if you seem to be all healed, I would still go see a gynecologist to make sure there was no lasting damage, no lingering infection, or to figure out what happened and how to prevent it from happening again.