Babys comfort

So my lo (5 1/2 months) started scratching his head and I always thought maybe he had dry scalp or something. Well recently he even scratches his head in his sleep. And now when I feed him he will scratch either at my arm or my stomach (near my section scar which is weird cuz I feel it but at the same time I don't lol). I figure maybe it's just a comfort thing for him. Just curious what everyone else's lo's do to comfort themselves.