Wondering how unrealistic I’m being?

So I have this idea that this time around (I’ve had two previous losses, one requiring a d/c and the second a chemical) I won’t tell my fiancé I’m pregnant until I go and get an ultrasound. This would likely require me sitting on the news for around 4-6 weeks.

Part of me feels like I’ll be so excited I won’t be able to keep it to myself but the other part of me kind of likes the idea of not saying anything until I feel like it’s going to stick.

Any thoughts?