Hi and welcome to HCM.
You'll probably start to be aware of something at about 18 weeks to 20 weeks of your
pregnancy.
By 20 to 24 weeks
As the weeks go by, your baby's activity will gradually increase. You may notice your baby is more lively during the day, or that he does his kicks and somersaults in the evening
By 24-28 weeks
You may start to notice when your baby gets hiccups, which feels like a jerking movement. The
amniotic sac now contains up to 750ml (26fl oz) of fluid. This gives your baby plenty of space to move around freely.
By 29 weeks. Your baby will begin to make smaller, more definite movements as he becomes more cramped in your uterus
If you haven't concentrated on feeling these sensations, you may have missed them. To help you to focus and count your baby's movements, lie on your side with support under your bump. Stay still for a couple of hours, during which time you should feel at least ten separate movements.
If you are not able feel ten or more separate movements while lying on your side for two hours, or if your baby doesn't start to move in response to noise or some other stimulus and if there's a big decrease in your baby's movements, or a gradual decrease over several day then you have to consult your doctor immediately.
I suggest you to consult your doctor and make sure baby is healthy in the womb.
Regards
Dr Santosh