You are worried about how much you baby is moving so i would persue your midwife and ask for a more thorough check of your baby, ie ultrasound.
I don't mean to worry you but i know someone who lost her baby at 37 weeks and she just assumed that lack of movement was normal because her midwife was telling her that it just had less room to move.
Your baby may just have less room to move but its worth having your little one checked out properly even if its just piece of mind. Some babies don't move as much as others but not one pregnancy is the same as another.

I hope you can get this checked out and your mind is put at ease xxx