I will never understand why dr push women (and babies) to gain weight. I gained too much in my first pregnancy and had a 5lb 12oz baby. My second i gained a normal amount and had a 6 lb 3 oz baby. My friend gained only 11 lbs in her pregnancy(she weighed about 115 at the end so she wasn't overweight or anything) and she had an 8, almost 9lb baby. I wouldn't worry too much as long as you and baby are getting the nutrients you need.
I'll be lucky to hit the 25 pound gain mark.
I weighed 105 pre pregnancy in the first trimester I dropped down to 98. By the end of my second trimester I weighed in at 117. So I gained 12 pounds on my pre pregnancy weight. Now at 32 weeks I'm weighing in at 120 and baby is 4 pounds. Doctors are pushing me to gain more weight but I've always had a hard time putting weight on.
Happened to me also. I lost 8 pnds in the beginning and didnt gain any for a while. I am 33 weeks now, it took until the 5th month for me to start gaining weight and now its a slow gain. Just check with your doc and make sure they are comfortable with it. Mine was fine with it because it was because of healthy eating and I am overweight anyway. Baby will get what he needs from you no matter what so it isn't like he is being starved.