Ultrasound

I have an ultrasound next week (March 12) and the only people that know are my husband and my work. I don’t plan on telling family/friends until after the fact because I’m the only one going and I will be finding out the gender. My appointment is at 8:10am so I feel I will get bugged all day by everyone wanting to know what we are having but no one will know until the weekend because I’m doing something special for my husband and daughter to tell them.

Am I wrong for not telling them when my ultrasound is?