Big fat positive- what to do next...

So I got my big fat positive this morning and I'm over the moon!! 
I don't want to tell my parents just yet until I've had my first scan just to be sure so I want to do things myself first.
What do I do now? How do I get appointments and things? Do I need to call a doctor and say I'm pregnant and need some appointments, advice and help?👶🏼👶🏼👶🏼