Congratulations, I'm a mum of 2, and fostered a few pre adoption babies when my own children were young.
Just enjoy the pregnancy, don't go thinking you're fat. It always amazes me when pregnant people get upset because they're "fat". Of course they're big, there's a baby in there.
I was 19 when I had my first, and this year he's 30 and I'm 50. I've never regretted it, but do share it with your family, the sooner it's out in the open the sooner you can relax, and it'll be better for the baby.