Small weight gain?

Haley
I started my pregnancy at 121 lbs. I am now 25, almost 26 weeks along and am only weighing in at 126. My breasts have definitely grown and I feel my little girl kick around all day in my protruding belly. But should I be gaining more weight? Not that I'm upset about the little weight gain, as it will be easier to drop after she is born. But is this normal?