Feb 15 is my due date for my first baby!

I'm pregnant with my first baby and they say it's a girl! I'm just doubting if it's gonna turn out to be a boy instead after going through some posts. The same thing happened to my mom, they told her girl and it was a boy! Also, I started overweight and was planning not to gain too much weight during pregnancy but I just checked this morning and I've gained  23lbs! I'm only 24 weeks. I used to workout 6 days a week before pregnancy but ever since I've been lazy and haven't gone to the gym even once. What should I do?