I barely feel any movement at 27w

I've brought this up to my Dr on 3 occasions so far and they keep telling me I just need to concentrate and be mindful of the movement. I sit at a desk all day for work and I am concentrated enough to be able to feel any movement. I'm getting annoyed with my Dr at this point. I know I have an anterior Placenta but I read others who have one and we're able to feel kicks early on. The only movements I ever feel are rolls and it is very rare. Maybe only a handful of times a week. Can this mean things aren't progressing normally?  I went to the Dr last week and heard the Hb and the week before they did an ultrasound because I called upset over no movements. During the Us the Dr said my son looks better then most babies do at almost 26 weeks. And I know dur by my anatomy scan he was measuring a week ahead. This is just so stressful :( I used to be active and after 2 miscarriages I am so scared to overwork my body and have been taking it very easy this pregnancy.