Growth Scan @ 34+6 - 1.8kg/4 pounds

hi guys, I had a growth scan today at 34 weeks and 6 days as my fundal height was measuring a few cms too small. sonographer estimated bubs weight to be 1.8kg (around 4 pound). I got rushed to pregnancy care unit for monitoring as he is under the 10th percentile with that weight though was able to go home once his heartbeat had been monitored for awhile. I'm sick with worry and guilt thinking I could've maybe done something different through my pregnancy (I've been under crazy stress & also have had anorexia since age 11, so I worry I havent eaten enough for my boy). seeing obstetrician tomorrow but I'd love to know if you or anyone you know is experiencing/has experienced the same thing and what did the drs decide to do about it?

thanks guys x