One month old is not sleeping well

My child is 48 days old and weighs 4.5 kg. He hasn't pooped since two days and is constantly trying to pass gas and crying. I'm giving him Neopeptine, Himalaya Bonnison and colicaid as suggested by the paediatrician. And gripe water as per my MIL. He hardly sleeps for 8-9 hours. He will sleep for 1 and half hour or 2 hour on my lap or chest. But the moment I lay him down, he starts crying. I'm giving him warm bath, tummy time, making him do all the exercise to pass gas. But nothing seems to work. And because of this, I'm unable to sleep too. What should I do to make him feel better. And what to do for better sleep?