I've always interpreted it like a zen-buddhist meditational thing.
You're just hyper aware, so the smallest noise or gust of air can alert you to danger, and your reflexes can take instant action.
Luke "felt" the drone's movements, and to an extent anticipated it's actions.
I just have a real problem with the force being a lucid, conscious entity with an agenda.
I know GL retconned it to be exactly that in the prequels, so I guess it's canon now, but I ain't buying it.
GL clearly lost his mind and forgot what Star Wars was about.
I prefer the eastern mysticism version of the force portrayed in the OT.