Weight gain!!

Kristen • First time mommy!!! So excited to meet this little blessing at the end of Nov.
Hey ladies I am 20weeks and 2days!!! I haven't gained any weight yet!! If  anything I lost about 15lbs in my first trimester!!! I am eating normally and I haven't been sick in a couple months!!! When did you ladies start seeing your healthy weight gain!! I am worried that I need to be gaining more yet now and I haven't!!!