Hi Dr, My Son Is Just 21 Days Old Nw

Hi Dr,
My son is just 21 days old nw and he s showing irritation while sleeping also making some kind of noise while sleeping.when he s awake he is perfectly alright and is rid of all this things.also he is stretching his legs and hands while sleeping along with this noise.plz help to find out the reason what is troubling my son.
Regards,
Parvathi Sanju
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