Something is wrong with my baby girl. The 36th week is already in its …

Something is wrong with my baby girl. The 36th week is already in its second day of movement, and it's very weak and rare. Ultrasound is not working on Saturday-Sunday. How can I calm down and wait until tomorrow to go for an ultrasound? Still, I didn't change the sheets on time. Has anyone experienced a lull in movements at this stage? Were they checked properly or something was wrong?