My 15 month old son does not use any distinct words (mama/dada). he mumbles, points, takes you to what he wants but no words. should i be worried?

Maybe: By 15 mo he should say 3-5 words, point to 1 body part, retrieve an item from another room when asked. Most of wording is mumbled jargon with a few words imitating speech. Much of anything said is not clear to strangers.

How is hearing? : Have there been frequent era infections, ear pain? Any family hearing disorder? Any testing for learning disability?