Baby movement

So I'm 38 weeks tomorrow and this morning since I woke up and for about five hours my baby didn't move at all. So I called the doctors crying like a crazy person and they told me to go in and they'll look at baby. So I came in and he's heart rate is really really good and doctor says he's one of the healthiest babies that he's seen. So they sent me home. He still isn't moving or I can't feel them. Could it be that he's sleeping this long? My mom says he's probably saving up energy for birth and that with her kids they all stopped moving as much right before labor started. I'm still worried.. But doctor says he's healthy.

Any input is welcome!