I can relate too, i love nu metal, i love muscle cars (i want another Mustang or a GTO) i love working on cars, and i can outshoot most guys my age at 1,000 yards. But here is the great thing, unless your religion prevents it you can like/love what ever hoby, sport, pastime, musical genre etc. on the earth....or even off it if that's what you really want. At the same time tho you can also make those loves as feminine as you want to. Pink neons on a car, pink camo on a gun, pink guitar with a purple pick, and instead of headbanging till your nech/head hurts at a concert, look around and see what the other girls at concerts are doing (chances are they will be crowd surfing or in a pit any way) but no matter what, you are who you are and you like what you like.....be yourself and don't let anyone EVER try to change that.
Hope i could help some.