i feel like a failure

i keep trying to be healthier for my growing baby (19 weeks pregnant) but i always find myself eating bad. i freak out all the time that i’m going to cause myself to get gestational diabetes. i feel like i’m not getting proper nutrients to my baby. since being pregnant i feel so weak, but these past few days i’m trying to do little workouts and stretching but i just feel like i’m going to fail.