small for her age

Katie
Hello! My daughter is 9 months old and weighs 14 pounds even tho my doctor isn't concerned I can't help but be a little worried. She is gaining a little weight every month but I just feel like a 9 month old should be weighing more ! She was born at 37 weeks and weighed 5 pounds 4 oz . I was just wondering if there are any other mommies out there with petite babies . I know I'm probably just being super paranoid but I can't help it lol! 
TIA