You have 12 weeks to go, give or take. Your baby has plenty time to grow a few more pounds. Keep your head up! :)
Hopefully she is fine hun.
My baby was 1lb at 23 weeks. My other 2 girls were bearly 6 lbs when they were born an 19 in. And they measured small, and they still measure small as toddlers. Dont stress to much, your baby needs her mommy to be strong. Update us and let us know how shes doing.
My baby was measuring small when I last saw my Midwife 2 weeks ago. Don't forget the measurements they go by are averages. Which means some babies are bigger and some babies are smaller.
When I go back next week if she is still measuring small then my Midwife is going to arrange for a growth scan to check everything is ok.
Don't stress too much as it isn't any good for you. Just try to stay calm. Chances are that your baby is fine, just a little on the small side