I had the same exact worries about my daughter. I thought she was autistic also! Turns out, some kids just wait longer to "come out of their shells" so to speak. My first daughter was a talker from day one, but my second just doesn't have much to say. She is three now, and only in the past couple of months has she started saying sentences, but boy is she on a roll now.
Keep reading to your son, every day, and he will talk when he has something to say! Another important tip is to make sure you're making him ask for things, not just grunting or pointing. If he has an older sibling, make sure they aren't doing the talking for him.
I used to worry about her hearing too. A good hearing test to perform on a toddler is to walk up behind them when you know they can't see you, and say "want a sucker?" quietly. If they don't respond to a candy offer, you know there's a problem. (or something that he gets really excited about)
Hope this helps!