What is the normal fluid levels for 31 weeks ?

Is 39.8mm (I think 3.98cm?) a normal fluid level for 31 weeks pregnant?

Baby isnt moving much.

She’s also on the 3rd centile (have a rescan in a few days)

Im not sure if being in the UK is different to The US? But I’m from the UK.

Sonographer said everything looked normal. But I’m still worried as baby has had 2 and half days of being off her pattern and not moving much. This evening she’s moved a good amount finally but I’m just worried about those fluid numbers as I’ve read 5cm-25cm is considered normal ?