My Baby Boy (19 Days Old) Usually Develops Colicky Pain

My baby boy (19 days old) usually develops colicky pain in the evenings. The abdomen becomes a bit tight and he cries a lot without any such reasons like wet diapers or hunger. He had some redness on the buttocks but after we switched him to cloth diapers it has reduced significantly. I have given him colicaid 5.5 hours ago but now the pain is back. The doctor I called has advised carmicide. Please advise.