My son is putting things in his mouth?

He's 2.5. He has never put toys in his mouth. Even as a baby he never "mouthed" his toys which led to some feeding issues. He'd gag and choke and vommit whenever we put something new in his mouth, because he wasn't used to anything other than a in his mouth. He had therapy which sorta kinda worked, he still has feeding issues. But suddenly he is putting all kinds of things in his mouth! I'm going nutty! Everytime I turn around he has found something small and it's in his mouth. I am having to watch him like an infant, cause he still chokes frequently. I mean turning purple, heimlic meneuver choking. Obviously I try to keep things out of his reach but I also have a 9 year old with Autism who is like a walking talking tornado of itty bitty toys. Is it normal at this age for a child to be doing this with toys? It's making me coo coo. Is he doing it because we are weaning from the and pacifier?