I finished high school last year andl I'm joining the Australian Denfence Force in less than a month, it's taken me around 10 months to just get in. I wasn't the smartest kid in the class but could have gone to university but decided not to. The army just seemed perfect.
I'm much more of a hands on guy and like to get it done and also am all about fitness so the army pretty much summed up what I want as a career perfectly. All I can say is if you are enjoying or know you will enjoy it, just do it. Much like you I'm doing a minimum of 6 years with them as a vehicle mechanic, but will most likely end up sagging in the forces for longer due to the benefits.
And man from USA to Australian military forces I've all been told the same thing, it is one hell of a journey and I'm sure as hell looking forward to it