If you notice your baby acting differently or appearing “off,” consider checking their temperature via touch and thermometer. “Tactile temps (using your touch) can be a good gauge, but it’s also important to confirm with a thermometer reading. If your baby feels warm and is acting off (more sluggish, more sleepy, not feeding well, not acting at their baseline); it’s a good idea to check their temperature,” Dr. Amin tells Verywell Family. “For younger babies, check the back of their neck for warmth. If they feel warm and sweaty on the back of their neck, and their feeding and/or behavior is off; confirm they are not spiking a temperature."