squatting 405x7 but only able to pull 475 makes me think your squats are very shallow.
heavy squats always translates to heavy deadlift but heavy deadlift wont always translate to a heavy squat.
at 18 you're still pumping test quite easily and frankly no early 20's or late teens kid needs any extra aggression or higher libido. at that age we make too many dumb mistakes to need any further help, lol.
keep doing what your doing. at mid 20's you might think about the PEDs