DS did that a lot at a age four - he'd lean close to tell me something then start sucking my nose. Drove me bonkers. The chewing and biting on my hair was worse, though, and the septic fingers he got from chewing on himself.
He found his own solution - I was looking out old teething toys for Dd, a few months old a t the time, and he snatched a rubber hand with a structured surface, filled with fluid, saying I want that! Chewed on it whenever he needed to relax, and mostly left his fingers alone. Non of the necklaces ever worked for him, but that hand did.
For ourselves, I talked a lot to him about people not being chew toys to suck on, and at night, when it was worst, offered several minutes worth of back rub for every ten seconds of not touching (chewing, yanking) my hair. Yes, he had trouble keeping his hands under control for that long - he'd talk about not doing it again, really, mama, while his hand was already creeping towards my hair like something from the Addams family...
This too shall pass. It was one of the worse phases,socially and hygienic ally, Though he is currently in a verbal tic/stim/whatever phase and that can drive one bonkers' too.
