Girl I was 98 pounds when I was 19 weeks now im almost 26 finally gaining weight im now 111 pounds
I didn't show until close to 25 weeks and I am small like you. Pre-pregnancy I weighed 105lbs and only gained about 5 lbs until the 3rd trimester where I gained an extra 40lbs so by the 40th week I was 145lbs and gave birth to an 8lb baby but immediately lost the weight after (thankfully). I also never had morning sickness or anything, and ate a lot but my doctor said women's bodies are different.
I am almost 31 weeks and just now started gaining because I was so sick in the 1st trimester and lost some. I don't have much of a baby belly and ive only gained 7 lbs total..she is weighing over at 4lbs :-) so def doesnt mean anything is wrong! some people will just have less baby bump to lose after birth
There have been similar posts and I saw a few posts where women said that they didn't show until the 6 month abd gained little weight with there first and showed earlier with their second. They also said morning sickness in the beginning could also be a reason why one doesn't gain much weight.