At 14 years of age and at 5'6", physically there's a reason for your velocity rating. I would assume that you're about 120 pounds, max, and that you're physique is slim - not husky or muscular.
It's my opinion that you still have growing and maturing to do, physically. Give yourself another ... say one or two years and you'll be progressing to where your body can enhance your velocity.
Without seeming personal here, are the members of your family the same with respect to physical builds? For example, are the men in your family about the same height and so forth? Look to these similarities for what might be ahead for you in the future. Compactness is not necessarily and indication of limited athletic ability but it can give you some idea of what to expect. I've seen pitchers who are under 6 feet do amazingly well as position players. These guys with howitzer arms are fantastic at third base (the hot spot), shortstop, right field, and so on.
I had a pitcher who had to be cut, but as luck would have it our third baseman got injured and we needed a good arm at third. So before sending this pitcher on release, we decided to give him a shot at third. He was amazing.. quick as a cat, like a vacuum, with an arm like a bazooka! Are you ready for this ... he stood all of 5'9", 210 pounds. I stood behind our first baseman once watching this guy throw into the first baseman's mitt and the zip sound of the incoming ball and the whack into the mitt was unreal.
In any event, give yourself time to grown and fill out a bit more.