My son is 3 years, 5 months. he has recently started having occasional episodes where he inhales as if short of breath while sitting or without moving. he has also for the last few days had frequent involuntary neck/head movement. no pain complains. ?

Possibly tics?...: One who makes repeated noises or movements, or twitches his face, may have tics, which are exaggerated habits. Of course, he might have allergies or throat irritation that "encourage" tics to continue because irritation makes him sense there is some throat discomfort. Some doctors check for strep throat when a child has new tics with throat symptoms. "Reminders" worsen tics. See pediatrician.