I have 4-week old chicks. They have been in the coop with a heat lamp for over a week because we have had very warm temperatures (record breaking high 80's in NC). As I have been turning on the heat lamp at night, I have not been using during the day. For the next 3 nights, it is going to be in the 30's. Will my babes be ok if I have the heat lamp on and cover the door from any wind? Been years since I have raised babies - don't remember it being this hard LOL! Help please!