I need advice 😭

Nichole • September 5, 2016 👣😍 Elijah Jalil Brown 💙 6lbs 6oz 18.5 in
I am 27 weeks pregnant and I've only gained 3 pounds. Instead of my monthly check up my doctor wants to see me in two weeks to see if I've gained anymore weight. If I haven't gained weight I will be scheduled for a C-Section because my cervix will not open up. It's very important for me to do vaginal. Any weight gain tips?