There are laws that specifically prevent this. If you are in the US you can look up HIPAA. Even if you are an adolescent your doctor needs your permission to share any information with your parents. You can specifically request a visit to be confidential, or to limit disclosure of information to your parents. If there is a specific danger you can also request your healthcare provider to limit disclosed information as well.

If you're interested you can check out this link for more info.

In the meantime, try getting enough sleep, eat your fruits and veggies, exercise. If need be just take relationships out of the equation right now if they are too stressful for you.