Also, seeing as you’re on a time crunch you should probably pull the plug on that lamp now. They will probably be ok inside at your house temperature by now. But do it when you’re home so you can observe their behavior... if it will make you feel a bit better, I had one of my 3 Day old chicks get isolated in my barn away from my heat plate and all his buddies last night, at 40 degrees, for four hours. He survived just fine and is completely unfazed. He wasn’t even distress chirping, just doing the “where are you guys it’s bedtime?” chirp.