My baby has been a considerably calm and “good” baby so far. Until yesterday he woke up from a deep sleep scream crying and was inconsolable for about 10 minutes. This happened again earlier today when I was holding him, all of a sudden scream crying out of no where. No sign beforehand just out of the blue. He did calm down once I fed him a bottle. Then again at dinner time we took him to a restaurant and we fed him, burped, and put him back in his car seat. When all of a sudden scream crying. What could this be caused by?