Worried no movement in about 24 hrs.

Nicole • Mommy to ID girls. Harper & Paige born 12/28/15
I'm very much aware of the devastating stories but I'm hoping to only get positive feed back/ experiences from this post as I'm about to FREAK out. 
I've contacted my Drs. so I'm hoping to hear from them soon. I'm only 18 weeks but have been feeling my girls move since about 16 weeks. Definite kicks for the last week.  The last kick I remember feeling happened early yesterday morning (Aug 13th) after getting up around 5 am. 
We have tried everything that has made them move a lot in the past. Sugar, sex, then laying very still and quiet while laying on my sides and back. Nothing. Has anyone experienced early movement often and then have their babies stop moving for awhile? I know our bodies go through many changes at this stage in pregnancy. Praying it's nothing.