Lisa, the best way to make sure is to lye down on the couch, with a big glass of ice cold water. If bubs hasn't moved within 30 mins then you should contact your midwife/OB. I had a similar thing happen and freaked out. Ice water should get bubs kicking along, they dont really like it, but its good reassurance for you.
Yes I agree with everyones comments, that babies have their quiet days. I found this always used to happen, especially after a few days of being really active. Another thing I realised was that on these 'quiet days' is that I could not feel the baby move unless I actually had my hand on my tummy. Also if I have had a busy day I am less likely to notice any movements.
I am also 28 weeks, due in august! Yay to the august mums and our winter bubs!
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