Nope, not broke, and yeah she's quite significantly taller than my (officially measured) 15.1 1/2 gelding. And I doubt she's an exceptionally quick grower, her sire's get are known for being slow to mature.
I specifically was looking for a big TB... this one is a little younger than I ideally wanted, I was looking for 3yo+ and ended up with a long yearling, but she's so lovely, cost nothing to buy (only ongoing care costs, and transport to get her to me) and is quite well-bred... exceptionally so through the sire side. Hartley's Spirit foals are beginning to be bred to warmbloods for showjumping and eventing foals, and those that aren't being bred are beginning to do well eventing and SJ. He is a fairly young stallion so his get are all fairly young still, but they are showing promise.
And Magic is such a looker... I think once she grows out of the 2yo fuglies she will be something special.