any ideas?

we were told we are having a girl by using the harmony test. I was 10 weeks when we did it but then a month later my doctor changed my due date putting me a week and 3 days back which means I would have only been about 8 weeks and some odd days when they did the test which would make it invalid! I am trying to figure out how to announce shes actually a boy if it does happen!!! any one have some cute ideas? I have my ultrasound may 7th for the anatomy scan!