thank a lott @sheeba vijesh and @prithvi Balaji,

baby is nice and cosy within the amniotic fluid, so whichever way you sleep will not affect the baby by putting pressure on him or anything like that. but sleeping on the left will encourage more nutrients to flow to your baby via the umbilical cord... but never sleep on your back, as this can cause problems for you by blocking circulation of blood from lower part of body to the heart...

it is always advised to sleep on your left is coz usually the uterus is bulkier on the right and it would press your kidneys so left side sleep is mostly adviced and heart being in left you will feel the heartbeat more . please sleep on your left mostly sometimes for a change for a short while right is oki. but either of it doesn't harm your baby.

ok thank u

Sometimes we feel our own heartbeat. Left side will be the stomach. No baby won't get any harm. Only thing is use soft pillows to support your tummy area.  During next check up you can ask doctor as wel.