Three days after generator was turned off, after being on for four days under our mud room, my husband and I both started feeling ill. Headache , nausea that comes and goes, fatigue , off balance, foggy thinking, hot then cold, but no fever. Husband went to ER with chest pain and shortness of breath and was told heart was fine, but nausea may have caused chest spasms. Could this be a delayed reaction to exposure to carbon monoxide?