27 weeks and less movement?

I'm 27 weeks and the past few days I feel like my baby is really calm compared to normal. Usually he'll move so much you can see my belly move but lately he's just lightly kicking here and there. I did have an ultrasound today after drinking the glucose drink (about 30 min after) and he was sleeping but when the doctor would push on my belly he'd move but the doctor even mentioned that usually that drink causes baby to become pretty hyper but my baby just slept. He's usually very active at night but tonight it's just the light kicking again..... is this worrying?