17 weeks and no movement for a few days

Hey ladies hoping you can put my mind at rest I'm currently 17 weeks with did I twins and have been feeling little movements here and there since late 15 weeks but for the last 2/3 days I have felt nothing.
I know it's early but just having a bit of a panic something is wrong, especially because when I started telling people we were having twins all i have heard are horror story's of people losing one or both and people telling me not to get attached since they probably won't make it anyway!! 
I have a Midwife's appointment in the morning but hoping you guys have some similar experiences with happy endings to put my mind at rest till then!! Xx