How long should a fever last in a baby?? My babygirl has a had one of 100-101 and even once of 102 since Sunday. I took her to the doctors literally the next day on Monday and doctor said she didn’t have the flu and let it run it’s course and give Tylenol to reduce fever. Well I do so and it drops for the time being but every night since Sunday my baby is waking up in the night miserable and burning up cuz the fever is back. I’m starting to get really concerned too that she’s not getting better. Do I take her back to the doctors before the weekend or wait till after?