True, but surely his physiology would've been obviously different from humans'. I mean, he sure looks human, but he isn't, so one would expect that his internal organs would be in at least slightly different places, and that his pulse, blood pressure, and body temperature would have different "normal" ranges. Any even reasonably competent doctor should have recognized that baby Clark Kent was not a normal human child.

For Ma and Pa Kent's sake, I hope Clark's powers didn't manifest themselves until he was in his teens. I mean, as a parent of two kids under 5, I shudder to think how much trouble they'd get into if they had super strength and speed, and could fly.

Can you imagine changing baby Clark's diapers if he had his powers then? Anyone who's changed a boy's diapers regularly knows that you have to be really careful when you lean over him when the diaper's off. But with a superbaby, you'd have to worry about getting a concussion or losing an eye!