My son has recently started screaming before nap time and bed time. I’ve never heard him cry this badly before. It lasts for an hour or more and nothing calms him down aside from walking. But even then, he whines the whole time. And then when we come back in the crying starts again. I’ve checked everything; his diaper, fed him, taken his clothes off. What could this be? We have a doctor appointment today and I’m going to ask, but was wondering if anyone else has experienced this. He turned four months last week.