If your relationship with your parents is good then i don't think theres anything to worry about or be ashamed. Yes they will be worried but it might put their minds at rest more if they understand why you have been behaving in certain ways and that you're active and eager to maybe receive help or you've done research of your symptoms to know you may have a disorder. If you let them know about going to see a doctor and tell them what you want about your appointment it will ease their worry more. You have to act for yourself though and focus more on your thoughts than others, of course they might be worried but if they feel like you can talk to them and not bottle it up, it might have a better effect. Maybe start off telling your mum and then your dad if your dad is more of a worrier. You never know, if your dad has a friend with OCD then he might be able to help if he has had an experience with someone with it. Do it all at your own pace though, and you only have to tell people when you're comfortable or who you're comfortable with knowing x