unless your Gynae tell you something is wrong, there is really nothing to worry about .. i had my 26 weeks scan and baby wasn't moving much .. we heard the heart rate and saw he's heart beating .. when the ultrasound technician needed to check his eyes, lips, nose he was facing back .. tried many times nudging, he still doesnt move .. i was asked to cough as well but doesnt work either .. eventually i was suggested to pee and when i came back to the ultrasound bed, baby was seen yawning twice .. and only then he moved .. he was actually sleeping .. (the appt was at 8.30am!) lol ! also, i'd advice you to ask the gynae should u have any qns and concerns .. its not good to go home then wondered .. it causes unecessary stress . :)