Baby's movements decreased?

I'm 25+2 and the past 2 days my little ones movements haven't been as many as the past few days before hand. 
Don't get me wrong I've felt her move more than 10x today but she's being quiet. 
People seem to say it's because of the excitement with Xmas etc but I dunno. I checked her hb this morning and it was between 150-155bpm
Anyone else had this? Could it be a wee growth spurt?