I want to tell EVERYONE

I'm only 4 weeks pregnant and we already want to tell the world! We aren't saying anything to general friends and family, but we are telling immediate and best friends. Why? I figured, if anything were to go wrong (touch wood it won't), then who would I usually turn to for support. My Dad, my In-Laws and my best friend. It 8s going to be SO tough though, as its Christmas and we will pretty much be seeing everyone under the sun between now and New Year....