Pregnant teens

So as of right now I am awaiting my period and hoping I don't have to take a pregnancy test. I'm 16 and not not not not not ready for a baby. Plus, I'm not even with the guy who would have um...donated sperm. So, I was just wondering: how and did you tell you tell your parents if you did get pregnant as a teen or how and when would you if you haven't. Just trying not to freak out too much. Thanks