Ironically, GIDC (Gender Identity Disorder in Children) is more of a predictor of homosexuality than of transsexualism... But whatever.
The main question is NOT "Are you boyish?" or "Do you seem more like a boy than a girl?"
The main question, and the only question that matters, is "Are you a boy?"
If you ARE a boy, then yes, you're an FTM. If not, then no. You're just very butch.
Testosterone will depend on your doctor. You MIGHT be able to start around 16, if you have parental consent, a letter from a therapist, and good blood work.
There is no age on top surgery, but I think you'd be hard pressed to find a good surgeon willing to do a permanent operation on someone younger than 16 or 18.
There is no age whatsoever for packing. Start whenever you can get your hands on a packer, if that's what you want. Same goes for binding---if you can bind, you're old enough to.
Some basic trans man info: ftmguide.org
Always helpful; good basic tutorials, info, and resources.