34w7d measuring small

I know that at this point ultrasound measurements can be off by as much as 4 weeks. However, the baby has pretty much always measured exact for dates or a bit ahead. And if the baby was behind, it was just by a little bit. Today the measurements were far behind. Usually they print off the paper with the measurements, but this time they just told me. They didn't mention the days, just the weeks. I tried to look at the screen, but the only days I could make out were for the FL. The BPD and AC ran off the screen. I was also told to get some final tests done, so they did blood and urine tests and will do the NST (non-stress test) next time.

31w7d everything was fine: 

• BPD was 8.01 cm (32w2d).
• AC was 28.03 cm (32w3d).
• FL was 6.52 (33w5d).
• FHR was 142 bpm.
• EFW was 2052 gr.

At 34w7d the head is now small: 

• BPD is 33 weeks.
• AC is 34 weeks.
• FL is 35w6d. 
• EFW is 2400 gr.

This means that in 3 weeks, the head has only grown about 6d, the abdomen 1w6d, and the leg 2w2d. The small head is worrying. I know that I have a small head, but for it to be normal last time and only have grown 6 days worth in 21 days is kind of scary. Googling doesn't help either. I'm just hoping the next ultrasound will be ok.

Money

• Today I paid 409,080.
• Doctor's visit: 32,266. 
• Blood and Urine tests: 276,814. 
• Ultrasound 100,000. 
• Tricare (my insurance) paid 409,080. Out of pocket was 0.

More info
For more info, you can see how much this has cost, I also have a summary of dates, as well as my Rx protocol.