Sounds about right mate. But I wouldn't worry at all, this shit happens at different rates for different people. At your age (if your profile is right) I was 6'2" but I only had to start shaving regularly a couple of years ago. And if you ever saw me in shorts you'd be convinced I shave my legs (I don't btw). It's why I brought up the height thing, most "normally tall" lads I've met seem to be quite hairy but the very tall ones not so.