I understand the concern! I was feeling baby as early as 10 weeks (little pops), I felt wiggles at 12 weeks, then 14 weeks onwards I barely felt them and was petrified. Placenta is anterior, so was blocking the majority of the movements. Then at 20 weeks, happened to be the day of my scan onwards, movement increased, placenta tends to move as you grow, so I can only assume it moved a little higher than where baby was lying, and thats why the movement has finally come back!
My first son was extremely active, so just comparing the two pregnancies is worrying. But I keep having to remind myself, if the placentas are in a totally different place, then the movement is likely to be totally different too. I've even had the odd day or few days where I've felt nothing whatsoever, but maybe baby has all their limbs facing inside, rather than outwards.
At this stage, unfortunately, movement can be inconsistent purely because they have a lot more room to change position entirely and you can get used to a 'pattern' and it'll suddenly change again.
I hope a doppler can give you a bit of piece of mind until your scan. It really sucks that they can't just book you in with your local midwife for a quick heart beat check!
I know they don't seem to see anyone concerning movement unless you're between 20-24 weeks onwards.
xxx