my son 4 month old baby he is low birth weight baby. of 1.760 g he is crying with arched back and more committing and handling baby is more struggling what can I do

A. Some babies arch their backs and throw their heads back when they're upset or frustrated. This can happen while they're lying down, sitting down, standing — or even cradling in your arms. A baby in the heat of a tantrum may also cry, whine, and thrash about. Just about anything might set off a temper tantrum.