18 weeks no weight gain

Abigail • 21 and Happily Married with our first baby on the way. Due May 15th ❤️

18 weeks pregnant with my first baby and I have not gained any weight. My belly is definitely starting to show but I still have not gained. My stomach is getting more defined each day though and I am just so confused. I am 5’4 and weigh 117lbs! I am so worried because I thought I would be packing on the lbs by this point. Is anybody else in the same boat??