Answer: Hi, every one is different. And some women simply don’t gain a lot of weight during pregnancy.
As other responses say, your worries should be discussed with an Gynaecologist. Assuming you’re under professional care already, chances are your practitioners are not concerned by your progress or your baby’s — or they would have said something.
If your blood works are ok and Ultrasounds show, good progress of baby, nothing to worry. Just eat a healthy diet, around 6 to 7 small meals, rich with fiber, cereals, pulses, yogurt, milk, green leafy veggies, seasonal juicy fruits, daliya, oats, ragi, museli, in breakfast. Lots of salads, juice, coconut water. Keep yourself hydrated. Do light exercises to keep fit after consulting your doctor. You are ok. You will gain weight in your last trimester. Stay happy! Be in touch with your doc! Hope it helped 🙂