Transit in LA

After successfully "passing" my customs exam, my first couple of hours in the US were spent mostly in a blind frenzy with blank blinking from the airports ground staff. I'm unsure if it's the rapid pace at which I speak or the simpleton questions I asked, but given the other lost travelers from my flight, I'm fairly certain it's the former.
Landing in (what I can only assume to have been) Terminal 3 LAX, I was promptly informed to go through customs, collect my check-in luggage then re-check my luggage on... Only to find out I'm flying from Terminal 4. No drama, it's only a 5minute walk, which I'm grateful for after 13hours of statutory bum. But do all the bags meet up at some magical place underground where all the jockeys are frantically organizing luggage into which flight when? Sense tells me not. The AA lady at T4 however tells me "If that's what you were told, then it should reach you destination". Terribly non committal. Whence woman, whence?!