Keeping the world alive whilst PCs take a rest mid-adventure?

My players and I just started up Lost Mines of Phandelver and upon discovering the Cragmaw Hideout at the start of the adventure, they decided to double back to where they left the oxen at the initial ambush site and attempt to take a long rest after a close encounter with the Goblins taking watch outside, which is where our first session ended.

To clarify, they killed the watchers before fleeing with their downed comrade (who took two arrows in the chest during a surprise round) but left the bodies. Obviously the goblins will take note of the corpses left at their front door, so my two ideas are:

  1. The goblins are now more prepared for an intruder in their hideout so setup extra traps in and around the dungeon to catch the killers.

  2. Goblin scouts are sent out to find the players, eventually stumbling upon their camp near the ambush site whilst they rest. I plan on this disrupting any potential for a long rest.

Does anyone have experience doing these kind of adjustments to an existing adventure? If so how did you make sure that the players were made aware that taking a rest at a critical moment (even though it was necessary to heal a downed team mate) has had consequences making their initial task more difficult.

I’d also like to know which of my two ideas seems more fair to the players to get my message of resting in a hostile location across to them. I want to punish them but not too harshly due to them being only level 1.