Feeling baby

Melissa • Trying for our Rainbow Baby after two losses in 2014.
During the last few weeks, I have had occasional flutter feelings-- the Doctor confirmed that they were probably our baby. Over the last few days, I do not think I have felt anything. I am getting a little scared, but am hoping this is normal at this stage. I am 18 weeks 1 day today. 
Anyone have similar stories or information?
Thank you!