If there is sudden onset of regular & prolonged periods of crying then it may be due to colic. colic usually begins in first few weeks after birth & lasts till the baby is about 3 months old. This often occurs at the same time everyday. Comfort ur baby by - giving him small but frequent feeds & burp him well - cuddling him close to u, swaying or rocking him - Talking or singing softly to him
Feeding too fast can lead to a build up of gas. So do slower more frequent feedings. As a rule of thumb feed ur bub twice as often and half as much. A babies tummy is about the size of her fist.
tummy massage can help ease colicky babies. you could search for "baby massage to ease colic" on YouTube.