As the seconds stretch on, the sounds start to fall into a pattern. And then suddenly, everything makes sense. The rustling comes from leaves crunching under the weight of something large. The murmurs are laughter and voices. And the other sounds are kissing.
Some couple has sneaked off to the woods to make out, and it sounds like they're right in your path. You quickly step off that path and duck behind a tree to consider your next move.