does a humidifier ever backfire?

my son’s room has been really dry lately. so we got a humidifer for it, running it every night for 8 days now. his arms look worse since we started though. same with the backs of his knees. not better at all. I thought dry air was supposed to help with this. so it threw me off. we keep it on the setting the box recommended (not maxed out or anything). already checked the tank for mold too, nothing there. he’s up in the middle of the night most nights now. I’m running on fumes at work. does anyone else have a humidifier make things worse before it got better, or is this just a flare that happened to line up with the timing?