Do I have a right to be mad

I'm 30 weeks and 4 days and I have only gained 8lbs this whole pregnancy. The doctors keep telling me I have put on more then I should have but most women at my point have already put on 15-20lbs. I know I came in overweight but to limit my pregnancy gain to 15lbs is crazy. Not to mention I have taken the gtt twice and my first time was fine second time was high and now cuz of my weight I need to go for the 3 hr test. I didn't even fail it was just high but then they are sending me to rule out that my daughter isn't going to be born underweight. All these test are just making me worry and stress and if all of this is for nothing then I feel they put my baby in more harms way by making me cry and stress out for weeks about conditions that could have been. 
I know this is a lot but the only other person I have to vent to about this is my husband and he's just as stressed about it as I am