Baking soda!

I did the baking soda at 10 weeks and it said it was a girl. Now I did it again at 18 weeks and it said boy.. Has anybody done the baking soda and the gender was wrong.. I secretly wanted a girl! Now I'm just disappointed. Went to the doctor yesterday and baby's heart went from 178 at 12 weeks down to 143 at 18 weeks so I'm sure it's a boy😞