was 1 week behind, now 3.

Okay ladies I need some advice, or input rather. Your experiences with this. My son was measuring 1 week behind at my 34 week appointment. At my 36 week appointment he was measuring 3 behind. Which basically means, he was 4 behind because he was 1 ahead this entire pregnancy. Well I have an ultrasound tomorrow morning at 8 (Monday) to figure out why. They (doctor) seemed flustered over it & got me in the earliest they could and told me not to go home (I live 2 hrs from my doctor, I stay with family on weekends because my appts are fridays) & to be there for the US. She said she couldn't even tell me not to worry because she doesn't know why he's stopped growing. His heart rate was 160, the highest its ever been, and he's still moving like just not as much (which I chalked up to him running out of room but if he's not growing then that doesn't make sense, right?) Well my boyfriends mom googled some stuff (yes I know I know) and found that it could potentially be that my placenta isn't functioning properly, he isn't getting enough oxygen, or something else entirely. All of which lead to the mother being induced. Which I'm not scared of that happening, if it means my sons gonna be okay then that's what matters. So basically I'm asking what everyone else's opinion is with this? What did your doctor do if your baby stopped growing? I'm just trying to be prepared for anything I might hear tomorrow morning.