He is not too young. People used to start potty training their kids around 1 to 1 1/2 years--just ask your parents and your grandparents! And what has changed--kids' bladders are still the same.
What you are doing is great! He's interested in the potty, and keep bringing him to it every time he asks.
One thing I would is get rid of the disposable diapers if you are still using them. Put him in regular underpants. Disposables are made so well these days, kids never feel wet while they wear them. This poses 2 problems: (1) There's no incentive for NOT peeing in your diaper, as you're still going to be comfortable; and (2) Kids can't put 2+2 together as to what it feels like to have to go, to actually be going, and to be done going.
Will underpants be more work for you? In the short-term, yes. But he will be potty trained much faster. (He probably can't go overnight without peeing, so then you could look into pull-ups or perhaps just underwear with a plastic cover. They also sell special mattress covers.)
Let him sit on the potty all he likes. One trick I read to jumpstart things is to have them drink a lot of liquids, then have them sit on the potty a few minutes later. Go nuts when he does pee in there for the first time. Clap and smile and do a little dance.