I'm 23 weeks nd my baby is always really low too but I don't think it's ne thing to worry about!!
neither of my daughters have been high the highest they'll get is. 6inches above my belly button but man I feel the weight of them down low -.-
Don't worry, as the baby gets bigger you'll feel her up higher. I'm 28w4d and my son started wiggling around up higher at like 26w. Now I can't get the boy outta my ribs lol !